diff --git a/all.sas b/all.sas
index f576caf..a2193c8 100644
--- a/all.sas
+++ b/all.sas
@@ -2441,25 +2441,27 @@ run;
   @brief Create a CARDS file from a SAS dataset.
   @details Uses dataset attributes to convert all data into datalines.
     Running the generated file will rebuild the original dataset.
-  usage:
+  Usage:
 
       %mp_ds2cards(base_ds=sashelp.class
         , cards_file= "C:\temp\class.sas"
         , maxobs=5)
 
-    stuff to add
+  TODO:
      - labelling the dataset
      - explicity setting a unix LF
      - constraints / indexes etc
 
-  @param base_ds= Should be two level - eg work.blah.  This is the table that
+  @param [in] base_ds= Should be two level - eg work.blah.  This is the table that
                    is converted to a cards file.
-  @param tgt_ds= Table that the generated cards file would create. Optional -
+  @param [in] tgt_ds= Table that the generated cards file would create. Optional -
                   if omitted, will be same as BASE_DS.
-  @param cards_file= Location in which to write the (.sas) cards file
-  @param maxobs= to limit output to the first <code>maxobs</code> observations
-  @param showlog= whether to show generated cards file in the SAS log (YES/NO)
-  @param outencoding= provide encoding value for file statement (eg utf-8)
+  @param [out] cards_file= Location in which to write the (.sas) cards file
+  @param [in] maxobs= to limit output to the first <code>maxobs</code> observations
+  @param [in] showlog= whether to show generated cards file in the SAS log (YES/NO)
+  @param [in] outencoding= provide encoding value for file statement (eg utf-8)
+  @param [in] append= If NO then will rebuild the cards file if it already exists,
+  otherwise will append to it.  Used by the mp_lib2cards.sas macro.
 
 
   @version 9.2
@@ -2472,6 +2474,7 @@ run;
     ,random_sample=NO
     ,showlog=YES
     ,outencoding=
+    ,append=NO
 )/*/STORE SOURCE*/;
 %local i setds nvars;
 
@@ -2484,6 +2487,8 @@ run;
 %if (&tgt_ds = ) %then %let tgt_ds=&base_ds;
 %if %index(&tgt_ds,.)=0 %then %let tgt_ds=WORK.%scan(&base_ds,2,.);
 %if ("&outencoding" ne "") %then %let outencoding=encoding="&outencoding";
+%if ("&append" = "") %then %let append=;
+%else %let append=mod;
 
 /* get varcount */
 %let nvars=0;
@@ -2610,7 +2615,7 @@ data _null_;
 run;
 
 data _null_;
-  file &cards_file. &outencoding lrecl=32767 termstr=nl;
+  file &cards_file. &outencoding lrecl=32767 termstr=nl &append;
   length __attrib $32767;
   if _n_=1 then do;
     put '/*******************************************************************';
@@ -4013,21 +4018,26 @@ create table &outds (rename=(
 %mend;/**
   @file
   @brief Convert all library members to CARDS files
-  @details Gets list of members then calls the <code>%mp_ds2cards()</code>
-            macro
-    usage:
+  @details Gets list of members then calls the <code>%mp_ds2cards()</code> macro.
+  Usage:
 
-    %mp_lib2cards(lib=sashelp
-        , outloc= C:\temp )
+      %mp_lib2cards(lib=sashelp
+          , outloc= C:\temp )
+
+  The output will be one cards file in the `outloc` directory per dataset in the
+  input `lib` library.  If the `outloc` directory does not exist, it is created.
 
   <h4> SAS Macros </h4>
   @li mf_mkdir.sas
+  @li mf_trimstr.sas
   @li mp_ds2cards.sas
 
-  @param lib= Library in which to convert all datasets
-  @param outloc= Location in which to store output.  Defaults to WORK library.
-    Do not use a trailing slash (my/path not my/path/).  No quotes.
-  @param maxobs= limit output to the first <code>maxobs</code> observations
+  @param [in] lib= Library in which to convert all datasets
+  @param [out] outloc= Location in which to store output.  Defaults to WORK
+    library. No quotes.
+  @param [out] outfile= Optional output file NAME - if provided, then will create
+  a single output file instead of one file per input table.
+  @param [in] maxobs= limit output to the first <code>maxobs</code> observations
 
   @version 9.2
   @author Allan Bowe
@@ -4037,6 +4047,7 @@ create table &outds (rename=(
     ,outloc=%sysfunc(pathname(work)) /* without trailing slash */
     ,maxobs=max
     ,random_sample=NO
+    ,outfile=0
 )/*/STORE SOURCE*/;
 
 /* Find the tables */
@@ -4048,16 +4059,28 @@ select distinct lowcase(memname)
   from dictionary.tables
   where upcase(libname)="%upcase(&lib)";
 
+/* trim trailing slash, if provided */
+%let outloc=%mf_trimstr(&outloc,/);
+%let outloc=%mf_trimstr(&outloc,\);
+
 /* create the output directory */
 %mf_mkdir(&outloc)
 
 /* create the cards files */
 %do x=1 %to %sysfunc(countw(&memlist));
-   %let ds=%scan(&memlist,&x);
-   %mp_ds2cards(base_ds=&lib..&ds
-      ,cards_file="&outloc/&ds..sas"
-      ,maxobs=&maxobs
-      ,random_sample=&random_sample)
+  %let ds=%scan(&memlist,&x);
+  %mp_ds2cards(base_ds=&lib..&ds
+    ,maxobs=&maxobs
+    ,random_sample=&random_sample
+  %if "&outfile" ne "0" %then %do;
+    ,append=YES
+    ,cards_file="&outloc/&outfile"
+  %end;
+  %else %do;
+    ,append=NO
+    ,cards_file="&outloc/&ds..sas"
+  %end;
+  )
 %end;
 
 %mend;/**
@@ -12278,31 +12301,20 @@ filename &fname1 clear;
 %mend;/**
   @file mv_getgroups.sas
   @brief Creates a dataset with a list of viya groups
-  @details First, be sure you have an access token (which requires an app token).
-
-  Using the macros here:
+  @details First, load the macros:
 
       filename mc url
         "https://raw.githubusercontent.com/sasjs/core/main/all.sas";
       %inc mc;
 
-  An administrator needs to set you up with an access code:
+  Next, execute:
 
-      %mv_registerclient(outds=client)
+      %mv_getgroups(outds=work.groups)
 
-  Navigate to the url from the log (opting in to the groups) and paste the
-  access code below:
-
-      %mv_tokenauth(inds=client,code=wKDZYTEPK6)
-
-  Now we can run the macro!
-
-      %mv_getgroups()
-
-  @param access_token_var= The global macro variable to contain the access token
-  @param grant_type= valid values are "password" or "authorization_code" (unquoted).
+  @param [in] access_token_var= The global macro variable to contain the access token
+  @param [in] grant_type= valid values are "password" or "authorization_code" (unquoted).
     The default is authorization_code.
-  @param outds= The library.dataset to be created that contains the list of groups
+  @param [out] outds= The library.dataset to be created that contains the list of groups
 
 
   @version VIYA V.03.04
diff --git a/base/mp_ds2cards.sas b/base/mp_ds2cards.sas
index a6d15b9..b56e84a 100644
--- a/base/mp_ds2cards.sas
+++ b/base/mp_ds2cards.sas
@@ -3,25 +3,27 @@
   @brief Create a CARDS file from a SAS dataset.
   @details Uses dataset attributes to convert all data into datalines.
     Running the generated file will rebuild the original dataset.
-  usage:
+  Usage:
 
       %mp_ds2cards(base_ds=sashelp.class
         , cards_file= "C:\temp\class.sas"
         , maxobs=5)
 
-    stuff to add
+  TODO:
      - labelling the dataset
      - explicity setting a unix LF
      - constraints / indexes etc
 
-  @param base_ds= Should be two level - eg work.blah.  This is the table that
+  @param [in] base_ds= Should be two level - eg work.blah.  This is the table that
                    is converted to a cards file.
-  @param tgt_ds= Table that the generated cards file would create. Optional -
+  @param [in] tgt_ds= Table that the generated cards file would create. Optional -
                   if omitted, will be same as BASE_DS.
-  @param cards_file= Location in which to write the (.sas) cards file
-  @param maxobs= to limit output to the first <code>maxobs</code> observations
-  @param showlog= whether to show generated cards file in the SAS log (YES/NO)
-  @param outencoding= provide encoding value for file statement (eg utf-8)
+  @param [out] cards_file= Location in which to write the (.sas) cards file
+  @param [in] maxobs= to limit output to the first <code>maxobs</code> observations
+  @param [in] showlog= whether to show generated cards file in the SAS log (YES/NO)
+  @param [in] outencoding= provide encoding value for file statement (eg utf-8)
+  @param [in] append= If NO then will rebuild the cards file if it already exists,
+  otherwise will append to it.  Used by the mp_lib2cards.sas macro.
 
 
   @version 9.2
@@ -34,6 +36,7 @@
     ,random_sample=NO
     ,showlog=YES
     ,outencoding=
+    ,append=NO
 )/*/STORE SOURCE*/;
 %local i setds nvars;
 
@@ -46,6 +49,8 @@
 %if (&tgt_ds = ) %then %let tgt_ds=&base_ds;
 %if %index(&tgt_ds,.)=0 %then %let tgt_ds=WORK.%scan(&base_ds,2,.);
 %if ("&outencoding" ne "") %then %let outencoding=encoding="&outencoding";
+%if ("&append" = "") %then %let append=;
+%else %let append=mod;
 
 /* get varcount */
 %let nvars=0;
@@ -172,7 +177,7 @@ data _null_;
 run;
 
 data _null_;
-  file &cards_file. &outencoding lrecl=32767 termstr=nl;
+  file &cards_file. &outencoding lrecl=32767 termstr=nl &append;
   length __attrib $32767;
   if _n_=1 then do;
     put '/*******************************************************************';
diff --git a/base/mp_lib2cards.sas b/base/mp_lib2cards.sas
index a5e6e1e..47172d7 100644
--- a/base/mp_lib2cards.sas
+++ b/base/mp_lib2cards.sas
@@ -1,21 +1,26 @@
 /**
   @file
   @brief Convert all library members to CARDS files
-  @details Gets list of members then calls the <code>%mp_ds2cards()</code>
-            macro
-    usage:
+  @details Gets list of members then calls the <code>%mp_ds2cards()</code> macro.
+  Usage:
 
-    %mp_lib2cards(lib=sashelp
-        , outloc= C:\temp )
+      %mp_lib2cards(lib=sashelp
+          , outloc= C:\temp )
+
+  The output will be one cards file in the `outloc` directory per dataset in the
+  input `lib` library.  If the `outloc` directory does not exist, it is created.
 
   <h4> SAS Macros </h4>
   @li mf_mkdir.sas
+  @li mf_trimstr.sas
   @li mp_ds2cards.sas
 
-  @param lib= Library in which to convert all datasets
-  @param outloc= Location in which to store output.  Defaults to WORK library.
-    Do not use a trailing slash (my/path not my/path/).  No quotes.
-  @param maxobs= limit output to the first <code>maxobs</code> observations
+  @param [in] lib= Library in which to convert all datasets
+  @param [out] outloc= Location in which to store output.  Defaults to WORK
+    library. No quotes.
+  @param [out] outfile= Optional output file NAME - if provided, then will create
+  a single output file instead of one file per input table.
+  @param [in] maxobs= limit output to the first <code>maxobs</code> observations
 
   @version 9.2
   @author Allan Bowe
@@ -25,6 +30,7 @@
     ,outloc=%sysfunc(pathname(work)) /* without trailing slash */
     ,maxobs=max
     ,random_sample=NO
+    ,outfile=0
 )/*/STORE SOURCE*/;
 
 /* Find the tables */
@@ -36,16 +42,28 @@ select distinct lowcase(memname)
   from dictionary.tables
   where upcase(libname)="%upcase(&lib)";
 
+/* trim trailing slash, if provided */
+%let outloc=%mf_trimstr(&outloc,/);
+%let outloc=%mf_trimstr(&outloc,\);
+
 /* create the output directory */
 %mf_mkdir(&outloc)
 
 /* create the cards files */
 %do x=1 %to %sysfunc(countw(&memlist));
-   %let ds=%scan(&memlist,&x);
-   %mp_ds2cards(base_ds=&lib..&ds
-      ,cards_file="&outloc/&ds..sas"
-      ,maxobs=&maxobs
-      ,random_sample=&random_sample)
+  %let ds=%scan(&memlist,&x);
+  %mp_ds2cards(base_ds=&lib..&ds
+    ,maxobs=&maxobs
+    ,random_sample=&random_sample
+  %if "&outfile" ne "0" %then %do;
+    ,append=YES
+    ,cards_file="&outloc/&outfile"
+  %end;
+  %else %do;
+    ,append=NO
+    ,cards_file="&outloc/&ds..sas"
+  %end;
+  )
 %end;
 
 %mend;
\ No newline at end of file