diff --git a/zipline/finance/trading.py b/zipline/finance/trading.py
index b610ea65..c9dde661 100644
--- a/zipline/finance/trading.py
+++ b/zipline/finance/trading.py
@@ -75,7 +75,8 @@ class TradingEnvironment(object):
         self,
         load=None,
         bm_symbol='^GSPC',
-        exchange_tz="US/Eastern"
+        exchange_tz="US/Eastern",
+        max_date=None
     ):
         self.prev_environment = self
         self.trading_day_map = OrderedDict()
@@ -94,6 +95,8 @@ class TradingEnvironment(object):
         self.exchange_tz = exchange_tz
 
         for bm in self.benchmark_returns:
+            if max_date and bm.date > max_date:
+                break
             self.trading_day_map[bm.date] = bm
 
         self.first_trading_day = next(self.trading_day_map.iterkeys())
diff --git a/zipline/gens/tradesimulation.py b/zipline/gens/tradesimulation.py
index dd409f05..09421d10 100644
--- a/zipline/gens/tradesimulation.py
+++ b/zipline/gens/tradesimulation.py
@@ -168,13 +168,8 @@ class AlgorithmSimulator(object):
                             yield daily_rollup
                             tp = self.algo.perf_tracker.todays_performance
                             tp.rollover()
-
                             if mkt_close < self.algo.perf_tracker.last_close:
-                                env = trading.environment
-                                _, mkt_close = \
-                                    env.next_open_and_close(
-                                        mkt_close
-                                    )
+                                mkt_close = self.get_next_close(mkt_close)
 
             risk_message = self.algo.perf_tracker.handle_simulation_end()
             yield risk_message
@@ -193,6 +188,12 @@ class AlgorithmSimulator(object):
             perf_message['intraday_perf']['recorded_vars'] = rvars
             return perf_message
 
+    def get_next_close(self, mkt_close):
+        if mkt_close >= trading.environment.last_trading_day:
+            return self.sim_params.last_close
+        else:
+            return trading.environment.next_open_and_close(mkt_close)[1]
+
     def update_universe(self, event):
         """
         Update the universe with new event information.