diff --git a/pandas/tseries/frequencies.py b/pandas/tseries/frequencies.py
index 957a934d13f09..7b5003fe424ad 100644
--- a/pandas/tseries/frequencies.py
+++ b/pandas/tseries/frequencies.py
@@ -361,8 +361,8 @@ def _get_freq_str(base, mult=1):
 
 
 from pandas.tseries.offsets import (Nano, Micro, Milli, Second,  # noqa
-                                    Minute, Hour,
-                                    Day, BDay, CDay, Week, MonthBegin,
+                                    Minute, Hour, Day, BDay, CDay,
+                                    WeekBegin, Week, MonthBegin,
                                     MonthEnd, BMonthBegin, BMonthEnd,
                                     QuarterBegin, QuarterEnd, BQuarterBegin,
                                     BQuarterEnd, YearBegin, YearEnd,
@@ -398,6 +398,7 @@ def _get_freq_str(base, mult=1):
     'Q': 'Q',
     'A': 'A',
     'W': 'W',
+    'WS': 'W',
     'M': 'M'
 }
 
@@ -414,6 +415,7 @@ def _get_freq_str(base, mult=1):
 _days = ['MON', 'TUE', 'WED', 'THU', 'FRI', 'SAT', 'SUN']
 for _d in _days:
     _offset_to_period_map['W-%s' % _d] = 'W-%s' % _d
+    _offset_to_period_map['WS-%s' % _d] = 'WS-%s' % _d
 
 
 def get_period_alias(offset_str):
@@ -423,6 +425,7 @@ def get_period_alias(offset_str):
 
 _lite_rule_alias = {
     'W': 'W-SUN',
+    'WS': 'WS-MON',
     'Q': 'Q-DEC',
 
     'A': 'A-DEC',  # YearEnd(month=12),
diff --git a/pandas/tseries/offsets.py b/pandas/tseries/offsets.py
index 79227f6de90a5..6f1696cba3dfe 100644
--- a/pandas/tseries/offsets.py
+++ b/pandas/tseries/offsets.py
@@ -24,7 +24,7 @@
            'YearBegin', 'BYearBegin', 'YearEnd', 'BYearEnd',
            'QuarterBegin', 'BQuarterBegin', 'QuarterEnd', 'BQuarterEnd',
            'LastWeekOfMonth', 'FY5253Quarter', 'FY5253',
-           'Week', 'WeekOfMonth', 'Easter',
+           'WeekBegin', 'Week', 'WeekOfMonth', 'Easter',
            'Hour', 'Minute', 'Second', 'Milli', 'Micro', 'Nano',
            'DateOffset']
 
@@ -1643,6 +1643,10 @@ def _from_name(cls, suffix=None):
         return cls(weekday=weekday)
 
 
+class WeekBegin(Week):
+    _prefix = 'WS'
+
+
 class WeekDay(object):
     MON = 0
     TUE = 1
@@ -2955,6 +2959,7 @@ def generate_range(start=None, end=None, periods=None,
     SemiMonthEnd,              # 'SM'
     SemiMonthBegin,            # 'SMS'
     Week,                      # 'W'
+    WeekBegin,                 # 'WS'
     Second,                    # 'S'
     Minute,                    # 'T'
     Micro,                     # 'U'