diff --git a/run b/run
index e26a851..26b61b5 100755
--- a/run
+++ b/run
@@ -208,6 +208,12 @@ __RUN() {
 	##########################################
 
 	local ENV_REQUIRED=$(__CHECK_ENV_REQUIRED && echo 1 || echo 0)
+	local REQUIRED_ENVIRONMENT_REGEX=$(eval echo '$SCWRYPTS_REQUIRED_ENVIRONMENT_REGEX__'$SCWRYPT_GROUP)
+
+	[ $REQUIRED_ENVIRONMENT_REGEX ] && {
+		[[ $ENV_NAME =~ $REQUIRED_ENVIRONMENT_REGEX ]] \
+			|| FAIL 5 "group '$SCWRYPT_GROUP' requires current environment to match '$REQUIRED_ENVIRONMENT_REGEX' (currently $ENV_NAME)"
+	}
 
 	[[ $ENV_REQUIRED -eq 1 ]] && {
 		[ ! $ENV_NAME ] && ENV_NAME=$(SCWRYPTS__SELECT_ENV)
@@ -225,6 +231,10 @@ __RUN() {
 		export ENV_NAME
 	}
 
+	[ $REQUIRED_ENVIRONMENT_REGEX ] && {
+		[[ $ENV_NAME =~ $REQUIRED_ENVIRONMENT_REGEX ]] \
+			|| FAIL 5 "group '$SCWRYPT_GROUP' requires current environment to match '$REQUIRED_ENVIRONMENT_REGEX' (currently $ENV_NAME)"
+	}
 
 	##########################################
 
diff --git a/zsh/lib/scwrypts/environment-files.module.zsh b/zsh/lib/scwrypts/environment-files.module.zsh
index 33f50e0..060bfe8 100644
--- a/zsh/lib/scwrypts/environment-files.module.zsh
+++ b/zsh/lib/scwrypts/environment-files.module.zsh
@@ -64,7 +64,11 @@ SCWRYPTS__GET_ENV_NAMES() {
 		ERROR 'environment initialization error'
 		return 1
 	}
-	ls "$SCWRYPTS_ENV_PATH/scwrypts" | sort -r
+	[ $REQUIRED_ENVIRONMENT_REGEX ] && {
+		ls "$SCWRYPTS_ENV_PATH/scwrypts" | grep "$REQUIRED_ENVIRONMENT_REGEX" | sort -r
+	} || {
+		ls "$SCWRYPTS_ENV_PATH/scwrypts" | sort -r
+	}
 }
 
 SCWRYPTS__INIT_ENVIRONMENTS() {