diff --git a/lib/fast_legs/base.js b/lib/fast_legs/base.js
index 94d047a..125bea4 100644
--- a/lib/fast_legs/base.js
+++ b/lib/fast_legs/base.js
@@ -22,6 +22,8 @@ Base.prototype.truncate = function(opts, callback) {
   if (typeof opts === 'function') {
     callback = opts;
     opts = {};
+  } else {
+    opts = _.clone(opts);
   }
 
   var truncateStatement = Statements.truncate(this, opts);
@@ -53,6 +55,9 @@ Base.prototype.create = function(obj, callback) {
       if (_.isFunction(opts)) {
         callback = opts;
         opts = {};
+      } else {
+        /* Do not modify opts, which may be global. */
+        opts = _.clone(opts);
       }
 
       if (finder === 'findOne') opts.limit = 1;