diff --git a/README.md b/README.md
index 05f033c..136ad17 100644
--- a/README.md
+++ b/README.md
@@ -223,6 +223,13 @@ or don't want to see. All options must be overridden in your **.zshrc** file.
 |--------|-------|-------|
 |`BULLETTRAIN_HG_SHOW`|`true`|Show/hide that segment
 
+### Command execution time
+
+|Variable|Default|Meaning
+|--------|-------|-------|
+|`BULLETTRAIN_EXEC_TIME_SHOW`|`false`|Show/hide that segment
+|`BULLETTRAIN_EXEC_TIME_ELAPSED`|5|Elapsed time of command execution
+
 ## Contributors
 
 That project was originally a fork from
diff --git a/bullet-train.zsh-theme b/bullet-train.zsh-theme
index f518bf8..c05aa35 100644
--- a/bullet-train.zsh-theme
+++ b/bullet-train.zsh-theme
@@ -244,6 +244,14 @@ else
   ZSH_THEME_GIT_PROMPT_DIVERGED=$BULLETTRAIN_GIT_PROMPT_DIVERGED
 fi
 
+# COMMAND EXECUTION TIME
+if [ ! -n "${BULLETTRAIN_EXEC_TIME_SHOW+1}" ]; then
+  BULLETTRAIN_EXEC_TIME_SHOW=false
+fi
+if [ ! -n "${BULLETTRAIN_EXEC_TIME_ELAPSED+1}" ]; then
+  BULLETTRAIN_EXEC_TIME_ELAPSED=5
+fi
+
 # ------------------------------------------------------------------------------
 # SEGMENT DRAWING
 # A few functions to make it easy and re-usable to draw segmented prompts
@@ -297,6 +305,22 @@ prompt_context() {
   [[ -n "$_context" ]] && prompt_segment $BULLETTRAIN_CONTEXT_BG $BULLETTRAIN_CONTEXT_FG "$_context"
 }
 
+# Prompt previous command execution time
+preexec() {
+    cmd_timestamp=`date +%s`
+}
+
+prompt_cmd_exec_time() {
+  if [[ $BULLETTRAIN_EXEC_TIME_SHOW == false ]]; then
+    return
+  fi
+
+  local stop=`date +%s`
+  local start=${cmd_timestamp:-$stop}
+  let local elapsed=$stop-$start
+  [ $elapsed -gt $BULLETTRAIN_EXEC_TIME_ELAPSED ] && prompt_segment yellow white "${elapsed}s"
+}
+
 # Custom
 prompt_custom() {
   if [[ $BULLETTRAIN_CUSTOM_MSG == false ]]; then
@@ -519,6 +543,7 @@ prompt_line_sep() {
     echo -e '\n%{\u200B%}'
   fi
 }
+
 # ------------------------------------------------------------------------------
 # MAIN
 # Entry point
@@ -537,6 +562,7 @@ build_prompt() {
   prompt_go
   prompt_git
   prompt_hg
+  prompt_cmd_exec_time
   prompt_end
 }