diff --git a/2.7/Dockerfile b/2.7/Dockerfile
index 2ca772a..e56901f 100644
--- a/2.7/Dockerfile
+++ b/2.7/Dockerfile
@@ -47,7 +47,12 @@ RUN set -ex \
 		&& wget -O /tmp/get-pip.py 'https://bootstrap.pypa.io/get-pip.py' \
 		&& python2 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
-	&& pip install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/2.7/alpine/Dockerfile b/2.7/alpine/Dockerfile
index 302efee..2c53d0c 100644
--- a/2.7/alpine/Dockerfile
+++ b/2.7/alpine/Dockerfile
@@ -64,7 +64,12 @@ RUN set -ex \
 		&& wget -O /tmp/get-pip.py 'https://bootstrap.pypa.io/get-pip.py' \
 		&& python2 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
-	&& pip install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/2.7/slim/Dockerfile b/2.7/slim/Dockerfile
index 11a3922..6e656bc 100644
--- a/2.7/slim/Dockerfile
+++ b/2.7/slim/Dockerfile
@@ -60,7 +60,12 @@ RUN set -ex \
 		&& wget -O /tmp/get-pip.py 'https://bootstrap.pypa.io/get-pip.py' \
 		&& python2 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
-	&& pip install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/2.7/wheezy/Dockerfile b/2.7/wheezy/Dockerfile
index ac5182b..6c3b684 100644
--- a/2.7/wheezy/Dockerfile
+++ b/2.7/wheezy/Dockerfile
@@ -47,7 +47,12 @@ RUN set -ex \
 		&& wget -O /tmp/get-pip.py 'https://bootstrap.pypa.io/get-pip.py' \
 		&& python2 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
-	&& pip install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.3/Dockerfile b/3.3/Dockerfile
index c978436..ee30626 100644
--- a/3.3/Dockerfile
+++ b/3.3/Dockerfile
@@ -56,7 +56,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.3/alpine/Dockerfile b/3.3/alpine/Dockerfile
index b04660e..a4af101 100644
--- a/3.3/alpine/Dockerfile
+++ b/3.3/alpine/Dockerfile
@@ -73,7 +73,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.3/slim/Dockerfile b/3.3/slim/Dockerfile
index a12e09c..847fc3c 100644
--- a/3.3/slim/Dockerfile
+++ b/3.3/slim/Dockerfile
@@ -69,7 +69,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.3/wheezy/Dockerfile b/3.3/wheezy/Dockerfile
index ef0c415..46980f5 100644
--- a/3.3/wheezy/Dockerfile
+++ b/3.3/wheezy/Dockerfile
@@ -56,7 +56,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.4/Dockerfile b/3.4/Dockerfile
index c42717b..9fa0f70 100644
--- a/3.4/Dockerfile
+++ b/3.4/Dockerfile
@@ -56,7 +56,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.4/alpine/Dockerfile b/3.4/alpine/Dockerfile
index 19dc70c..b6c90b5 100644
--- a/3.4/alpine/Dockerfile
+++ b/3.4/alpine/Dockerfile
@@ -73,7 +73,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.4/slim/Dockerfile b/3.4/slim/Dockerfile
index 89699fd..4ef2a4d 100644
--- a/3.4/slim/Dockerfile
+++ b/3.4/slim/Dockerfile
@@ -69,7 +69,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.4/wheezy/Dockerfile b/3.4/wheezy/Dockerfile
index 72eb6bd..73d1c23 100644
--- a/3.4/wheezy/Dockerfile
+++ b/3.4/wheezy/Dockerfile
@@ -56,7 +56,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.5/Dockerfile b/3.5/Dockerfile
index b9aa4ce..69d9132 100644
--- a/3.5/Dockerfile
+++ b/3.5/Dockerfile
@@ -56,7 +56,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.5/alpine/Dockerfile b/3.5/alpine/Dockerfile
index d368cbb..bc2c41f 100644
--- a/3.5/alpine/Dockerfile
+++ b/3.5/alpine/Dockerfile
@@ -73,7 +73,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.5/slim/Dockerfile b/3.5/slim/Dockerfile
index d981a6a..111ff97 100644
--- a/3.5/slim/Dockerfile
+++ b/3.5/slim/Dockerfile
@@ -69,7 +69,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.5/windows/windowsservercore/Dockerfile b/3.5/windows/windowsservercore/Dockerfile
index 917dfb0..64c0187 100644
--- a/3.5/windows/windowsservercore/Dockerfile
+++ b/3.5/windows/windowsservercore/Dockerfile
@@ -42,7 +42,10 @@ RUN $url = ('https://www.python.org/ftp/python/{0}/python-{1}-amd64.exe' -f $env
 	\
 	$pipInstall = ('pip=={0}' -f $env:PYTHON_PIP_VERSION); \
 	Write-Host ('Installing {0} ...' -f $pipInstall); \
-	pip install --no-cache-dir --upgrade $pipInstall; \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	pip install --no-cache-dir --upgrade --force-reinstall $pipInstall; \
 	\
 	Write-Host 'Verifying pip install ...'; \
 	pip --version; \
diff --git a/3.6/Dockerfile b/3.6/Dockerfile
index 4797fa6..5e703d2 100644
--- a/3.6/Dockerfile
+++ b/3.6/Dockerfile
@@ -50,7 +50,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.6/alpine/Dockerfile b/3.6/alpine/Dockerfile
index 7314fb7..4c014f4 100644
--- a/3.6/alpine/Dockerfile
+++ b/3.6/alpine/Dockerfile
@@ -67,7 +67,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.6/slim/Dockerfile b/3.6/slim/Dockerfile
index 067dd29..ab7ade5 100644
--- a/3.6/slim/Dockerfile
+++ b/3.6/slim/Dockerfile
@@ -63,7 +63,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/3.6/windows/windowsservercore/Dockerfile b/3.6/windows/windowsservercore/Dockerfile
index 49b5104..b5fa44e 100644
--- a/3.6/windows/windowsservercore/Dockerfile
+++ b/3.6/windows/windowsservercore/Dockerfile
@@ -36,7 +36,10 @@ RUN $url = ('https://www.python.org/ftp/python/{0}/python-{1}-amd64.exe' -f $env
 	\
 	$pipInstall = ('pip=={0}' -f $env:PYTHON_PIP_VERSION); \
 	Write-Host ('Installing {0} ...' -f $pipInstall); \
-	pip install --no-cache-dir --upgrade $pipInstall; \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	pip install --no-cache-dir --upgrade --force-reinstall $pipInstall; \
 	\
 	Write-Host 'Verifying pip install ...'; \
 	pip --version; \
diff --git a/Dockerfile-alpine.template b/Dockerfile-alpine.template
index 22a7bae..5a9a60e 100644
--- a/Dockerfile-alpine.template
+++ b/Dockerfile-alpine.template
@@ -67,7 +67,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/Dockerfile-debian.template b/Dockerfile-debian.template
index f9df74b..56c6ef2 100644
--- a/Dockerfile-debian.template
+++ b/Dockerfile-debian.template
@@ -50,7 +50,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/Dockerfile-slim.template b/Dockerfile-slim.template
index c0ac725..1eb9bb1 100644
--- a/Dockerfile-slim.template
+++ b/Dockerfile-slim.template
@@ -63,7 +63,12 @@ RUN set -ex \
 		&& python3 /tmp/get-pip.py "pip==$PYTHON_PIP_VERSION" \
 		&& rm /tmp/get-pip.py \
 	; fi \
-	&& pip3 install --no-cache-dir --upgrade "pip==$PYTHON_PIP_VERSION" \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	&& pip3 install --no-cache-dir --upgrade --force-reinstall "pip==$PYTHON_PIP_VERSION" \
+# then we use "pip list" to ensure we don't have more than one pip version installed
+# https://github.com/docker-library/python/pull/100
 	&& [ "$(pip list |tac|tac| awk -F '[ ()]+' '$1 == "pip" { print $2; exit }')" = "$PYTHON_PIP_VERSION" ] \
 	\
 	&& find /usr/local -depth \
diff --git a/Dockerfile-windowsservercore.template b/Dockerfile-windowsservercore.template
index d74d0f9..01d1a8c 100644
--- a/Dockerfile-windowsservercore.template
+++ b/Dockerfile-windowsservercore.template
@@ -36,7 +36,10 @@ RUN $url = ('https://www.python.org/ftp/python/{0}/python-{1}-amd64.exe' -f $env
 	\
 	$pipInstall = ('pip=={0}' -f $env:PYTHON_PIP_VERSION); \
 	Write-Host ('Installing {0} ...' -f $pipInstall); \
-	pip install --no-cache-dir --upgrade $pipInstall; \
+# we use "--force-reinstall" for the case where the version of pip we're trying to install is the same as the version bundled with Python
+# ("Requirement already up-to-date: pip==8.1.2 in /usr/local/lib/python3.6/site-packages")
+# https://github.com/docker-library/python/pull/143#issuecomment-241032683
+	pip install --no-cache-dir --upgrade --force-reinstall $pipInstall; \
 	\
 	Write-Host 'Verifying pip install ...'; \
 	pip --version; \