diff --git a/load-env.cabal b/load-env.cabal
--- a/load-env.cabal
+++ b/load-env.cabal
@@ -1,5 +1,5 @@
 Name:                   load-env
-Version:                0.0.2
+Version:                0.0.3
 Author:                 Pat Brisbin <pbrisbin@gmail.com>
 Maintainer:             Pat Brisbin <pbrisbin@gmail.com>
 License:                BSD3
diff --git a/src/LoadEnv/Parse.hs b/src/LoadEnv/Parse.hs
--- a/src/LoadEnv/Parse.hs
+++ b/src/LoadEnv/Parse.hs
@@ -41,7 +41,7 @@
 identifier = do
     optional $ between spaces spaces $ string "export"
 
-    i <- many1 letter
+    i <- many1 $ letter <|> char '_'
     _ <- char '='
 
     return i