diff --git a/matlab/@dynSeries/align.m b/matlab/@dynSeries/align.m
new file mode 100644
index 000000000..d8b39b8ab
--- /dev/null
+++ b/matlab/@dynSeries/align.m
@@ -0,0 +1,123 @@
+function [a,b] = align(a, b)
+    
+%@info:
+%! @deftypefn {Function File} {[@var{a}, @var{b}] =} merge_dates (@var{a}, @var{b})
+%! @anchor{dynSeries/align}
+%! @sp 1
+%! If dynSeries objects @var{a} and @var{b} are defined on different time ranges, extend @var{a} and/or
+%! @var{b} with NaNs so that they are defined on the same time range.
+%! @sp 2
+%! @strong{Inputs}
+%! @sp 1
+%! @table @ @var
+%! @item a
+%! Object instantiated by @ref{dynSeries}.
+%! @item b
+%! Object instantiated by @ref{dynSeries}.
+%! @end table
+%! @sp 2
+%! @strong{Outputs}
+%! @sp 1
+%! @table @ @var
+%! @item a
+%! Object instantiated by @ref{dynSeries}.
+%! @item b
+%! Object instantiated by @ref{dynSeries}.
+%! @end table
+%! @end deftypefn
+%@eod:
+
+% Copyright (C) 2013 Dynare Team
+%
+% This file is part of Dynare.
+%
+% Dynare is free software: you can redistribute it and/or modify
+% it under the terms of the GNU General Public License as published by
+% the Free Software Foundation, either version 3 of the License, or
+% (at your option) any later version.
+%
+% Dynare is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with Dynare.  If not, see <http://www.gnu.org/licenses/>.
+
+if ~isequal(a.freq,b.freq)
+    error(['dynSeries::merge_dates: ''' inputname(1) ''' and ''' inputname(2) ''' dynSeries objects must have common frequencies!'])
+end
+
+init = min(a.init,b.init);
+
+time_range_of_a = a.init:a.init+a.nobs;
+time_range_of_b = b.init:b.init+b.nobs;
+
+last_a = time_range_of_a(a.nobs);
+last_b = time_range_of_b(b.nobs);
+
+
+common_time_range = intersect(time_range_of_a,time_range_of_b);
+
+if isempty(common_time_range)
+    error(['dynSeries::merge_dates: ''' inputname(1) ''' and ''' inputname(2) ''' dynSeries object must have at least one common date!'])
+end
+
+if a.init<b.init
+    n = b.init-a.init;
+    b.data = [NaN(n,b.vobs); b.data];
+    b.nobs = b.nobs+n;
+    b.init = init;
+end
+
+if a.init>b.init
+    n = a.init-b.init;
+    a.data = [NaN(n,a.vobs); a.data];
+    a.nobs = a.nobs+n;
+    a.init = init;
+end
+
+if last_a>last_b
+    n = last_a-last_b;
+    b.data = [b.data; NaN(n,b.vobs)];
+    b.nobs = b.nobs+n;
+    return
+end
+
+if last_a<last_b
+    n = last_a-last_b;
+    a.data = [a.data; NaN(n,b.vobs)];
+    a.nobs = a.nobs+n;
+end
+
+%@test:1
+%$ % Define a datasets.
+%$ A = rand(8,3); B = rand(7,2);
+%$
+%$ % Define names
+%$ A_name = {'A1';'A2';'A3'};
+%$ B_name = {'B1';'B2'};
+%$
+%$ % Define initial dates
+%$ A_init = '1990Q1';
+%$ B_init = '1989Q2';
+%$
+%$ % Instantiate two dynSeries objects
+%$ ts1 = dynSeries(A,A_init,A_name);
+%$ ts2 = dynSeries(B,B_init,B_name);
+%$
+%$ try
+%$   [ts1, ts2] = align(ts1, ts2);
+%$   t(1) = 1;
+%$ catch
+%$   t(1) = 0;
+%$ end
+%$ 
+%$ if t(1)
+%$   t(2) = dyn_assert(ts1.nobs,ts2.nobs);
+%$   t(3) = dyn_assert(ts1.init==ts2.init,1);
+%$   t(4) = dyn_assert(ts1.data,[NaN(3,3); A], 1e-15);
+%$   t(5) = dyn_assert(ts2.data,[B; NaN(4,2)], 1e-15);
+%$ end
+%$ T = all(t);
+%@eof:1
\ No newline at end of file