String Concatenation in SQL Group By clause

I got one problem in Ahmedabad SQLServer UserGroup.

The problem was something like... there are grouped data and requirement was making sum of string collection, means concatenation of string which are in the same group. Here is the question along with solutionSource Table

Field1     Field2
---------- ----------
Group 1    Member 1
Group 1    Member 2
Group 1    Member 3
Group 2    Member 1
Group 2    Member 2
Group 3    Member 1
Group 3    Member 2

Need output as

Field1     Field2
---------- ----------------------------
Group 1    Member 1,Member 2,Member 3
Group 2    Member 1,Member 2
Group 3    Member 1,Member 2

Solution:

SET NOCOUNT ON

--Creating Tables
DECLARE @Fields AS TABLE
(
    Field1 VARCHAR(10),
    Field2 VARCHAR(10)
)

--Inserting some values
INSERT INTO @Fields VALUES ('Group 1','Member 1')
INSERT INTO @Fields VALUES ('Group 1','Member 2')
INSERT INTO @Fields VALUES ('Group 1','Member 3')
INSERT INTO @Fields VALUES ('Group 2','Member 1')
INSERT INTO @Fields VALUES ('Group 2','Member 2')
INSERT INTO @Fields VALUES ('Group 3','Member 1')
INSERT INTO @Fields VALUES ('Group 3','Member 2')

--T-Sql
SELECT Field1, Substring(Field2, 2, LEN(Field2)) AS Field2 FROM
(
    SELECT
        [InnerData].Field1,
        (SELECT  ',' + Field2 FROM @Fields WHERE Field1=[InnerData].Field1 FOR XML PATH('')) AS Field2
        FROM
        (
            SELECT DISTINCT Field1 FROM @Fields
        ) AS [InnerData]
) AS OuterData