diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 582b714c882..89be9207545 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -48,6 +48,8 @@ Release 2.8.0 - UNRELEASED
     HADOOP-10300. Allowed deferred sending of call responses. (Daryn Sharp via
     yliu)
 
+    HADOOP-12366. expose calculated paths (aw)
+
   IMPROVEMENTS
 
     HADOOP-12458. Retries is typoed to spell Retires in parts of
diff --git a/hadoop-common-project/hadoop-common/src/main/bin/hadoop b/hadoop-common-project/hadoop-common/src/main/bin/hadoop
index 1575996bbb9..44be2e34f8b 100755
--- a/hadoop-common-project/hadoop-common/src/main/bin/hadoop
+++ b/hadoop-common-project/hadoop-common/src/main/bin/hadoop
@@ -38,6 +38,7 @@ function print_usage(){
   echo "                             YARN applications, not this command."
   echo "  checknative [-a|-h]  check native hadoop and compression libraries availability"
   echo "  distcp <srcurl> <desturl> copy file or directories recursively"
+  echo "  envvars              display computed Hadoop environment variables"
   echo "  archive -archiveName NAME -p <parent path> <src>* <dest> create a hadoop archive"
   echo "  classpath            prints the class path needed to get the"
   echo "                       Hadoop jar and the required libraries"
@@ -116,6 +117,15 @@ case $COMMAND in
       CLASSPATH=${CLASSPATH}:${TOOL_PATH}
     elif [ "$COMMAND" = "daemonlog" ] ; then
       CLASS=org.apache.hadoop.log.LogLevel
+    elif [ "$COMMAND" = "envvars" ] ; then
+      echo "JAVA_HOME='${JAVA_HOME}'"
+      echo "HADOOP_COMMON_HOME='${HADOOP_COMMON_HOME}'"
+      echo "HADOOP_COMMON_DIR='${HADOOP_COMMON_DIR}'"
+      echo "HADOOP_COMMON_LIB_JARS_DIR='${HADOOP_COMMON_LIB_JARS_DIR}'"
+      echo "HADOOP_COMMON_LIB_NATIVE_DIR='${HADOOP_COMMON_LIB_NATIVE_DIR}'"
+      echo "HADOOP_CONF_DIR='${HADOOP_CONF_DIR}'"
+      echo "HADOOP_TOOLS_PATH='${TOOL_PATH}'"
+      exit 0
     elif [ "$COMMAND" = "archive" ] ; then
       CLASS=org.apache.hadoop.tools.HadoopArchives
       CLASSPATH=${CLASSPATH}:${TOOL_PATH}
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs b/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
index fbfbaf2568f..714280e6a54 100755
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
@@ -47,6 +47,7 @@ function print_usage(){
   echo "  datanode             run a DFS datanode"
   echo "  debug                run a Debug Admin to execute HDFS debug commands"
   echo "  dfsadmin             run a DFS admin client"
+  echo "  envvars              display computed Hadoop environment variables"
   echo "  haadmin              run a DFS HA admin client"
   echo "  fsck                 run a DFS filesystem checking utility"
   echo "  balancer             run a cluster balancing utility"
@@ -161,6 +162,14 @@ elif [ "$COMMAND" = "haadmin" ] ; then
   CLASS=org.apache.hadoop.hdfs.tools.DFSHAAdmin
   CLASSPATH=${CLASSPATH}:${TOOL_PATH}
   HADOOP_OPTS="$HADOOP_OPTS $HADOOP_CLIENT_OPTS"
+elif [ "$COMMAND" = "envvars" ] ; then
+  echo "JAVA_HOME='${JAVA_HOME}'"
+  echo "HADOOP_HDFS_HOME='${HADOOP_HDFS_HOME}'"
+  echo "HDFS_DIR='${HDFS_DIR}'"
+  echo "HDFS_LIB_JARS_DIR='${HDFS_LIB_JARS_DIR}'"
+  echo "HADOOP_CONF_DIR='${HADOOP_CONF_DIR}'"
+  echo "HADOOP_TOOLS_PATH='${TOOL_PATH}'"
+  exit 0
 elif [ "$COMMAND" = "fsck" ] ; then
   CLASS=org.apache.hadoop.hdfs.tools.DFSck
   HADOOP_OPTS="$HADOOP_OPTS $HADOOP_CLIENT_OPTS"
diff --git a/hadoop-mapreduce-project/bin/mapred b/hadoop-mapreduce-project/bin/mapred
index 6f3bc04baf9..fd1300d67f7 100755
--- a/hadoop-mapreduce-project/bin/mapred
+++ b/hadoop-mapreduce-project/bin/mapred
@@ -38,6 +38,7 @@ function print_usage(){
   echo "                       mapreduce subcommands"
   echo "  historyserver        run job history servers as a standalone daemon"
   echo "  distcp <srcurl> <desturl> copy file or directories recursively"
+  echo "  envvars              display computed Hadoop environment variables"
   echo "  archive -archiveName NAME -p <parent path> <src>* <dest> create a hadoop archive"
   echo "  archive-logs         combine aggregated logs into hadoop archives"
   echo "  hsadmin              job history server admin interface"
@@ -75,6 +76,14 @@ elif [ "$COMMAND" = "sampler" ] ; then
   HADOOP_OPTS="$HADOOP_OPTS $HADOOP_CLIENT_OPTS"
 elif [ "$COMMAND" = "classpath" ] ; then
   echo -n 
+elif [ "$COMMAND" = "envvars" ] ; then
+  echo "JAVA_HOME='${JAVA_HOME}'"
+  echo "HADOOP_MAPRED_HOME='${HADOOP_MAPRED_HOME}'"
+  echo "MAPRED_DIR='${MAPRED_DIR}'"
+  echo "MAPRED_LIB_JARS_DIR='${MAPRED_LIB_JARS_DIR}'"
+  echo "HADOOP_CONF_DIR=${HADOOP_CONF_DIR}'"
+  echo "HADOOP_TOOLS_PATH='${TOOL_PATH}'"
+  exit 0
 elif [ "$COMMAND" = "historyserver" ] ; then
   CLASS=org.apache.hadoop.mapreduce.v2.hs.JobHistoryServer
   HADOOP_OPTS="$HADOOP_OPTS -Dmapred.jobsummary.logger=${HADOOP_JHS_LOGGER:-INFO,console} $HADOOP_JOB_HISTORYSERVER_OPTS"
diff --git a/hadoop-yarn-project/hadoop-yarn/bin/yarn b/hadoop-yarn-project/hadoop-yarn/bin/yarn
index 552cef41fae..5495387503c 100644
--- a/hadoop-yarn-project/hadoop-yarn/bin/yarn
+++ b/hadoop-yarn-project/hadoop-yarn/bin/yarn
@@ -89,6 +89,7 @@ function print_usage(){
   echo "  cluster                               prints cluster information"
   echo "  daemonlog                             get/set the log level for each"
   echo "                                        daemon"
+  echo "  envvars                               display computed Hadoop environment variables"
   echo "  top                                   run cluster usage tool"
   echo ""
   echo "Most commands print help when invoked w/o parameters."
@@ -217,6 +218,14 @@ if [ "$COMMAND" = "classpath" ] ; then
     echo $CLASSPATH
     exit 0
   fi
+elif [ "$COMMAND" = "envvars" ] ; then
+  echo "JAVA_HOME='${JAVA_HOME}'"
+  echo "HADOOP_YARN_HOME='${HADOOP_YARN_HOME}'"
+  echo "YARN_DIR='${YARN_DIR}'"
+  echo "YARN_LIB_JARS_DIR='${YARN_LIB_JARS_DIR}'"
+  echo "HADOOP_CONF_DIR='${HADOOP_CONF_DIR}'"
+  echo "HADOOP_TOOLS_PATH='${TOOL_PATH}'"
+  exit 0
 elif [ "$COMMAND" = "rmadmin" ] ; then
   CLASS='org.apache.hadoop.yarn.client.cli.RMAdminCLI'
   YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"