diff --git a/packages/behavior/item/condition.js b/packages/behavior/item/condition.js
index 7b5fe0c..bf10d87 100644
--- a/packages/behavior/item/condition.js
+++ b/packages/behavior/item/condition.js
@@ -65,6 +65,14 @@ export class Condition {
         }
         return true;
 
+      case 'contains':
+        if (this.operands.length < 2) {
+          return false;
+        }
+        const haystack = this.operands[0].get(context);
+        const needle = this.operands[1].get(context);
+        return -1 !== haystack.indexOf(needle);
+
     }
   }