diff --git a/bin/sassw b/bin/sassw
index 870bdde..acf3692 100755
--- a/bin/sassw
+++ b/bin/sassw
@@ -17,7 +17,8 @@ filename = sys.argv[1]
 def build():
     global sources, directories
     subprocess.call(['sassc', '-mauto', filename, filename.replace('.scss', '.css')])
-    sources = [os.path.abspath(x) for x in json.load(open(filename.replace('.scss', '.css.map')))['sources']]
+    basepath = os.path.abspath(os.path.dirname(filename))
+    sources = [os.path.abspath(os.path.join(basepath, x)) for x in json.load(open(filename.replace('.scss', '.css.map')))['sources']]
     directories = set([os.path.dirname(x) for x in sources])
 
 class EventManager(pyinotify.ProcessEvent):