Concatenate many rows into a single text string using SQL Server 2008

Here i will show how to Concatenate many rows into string using sql server 2008...

 Query :

declare @StringConc nvarchar(MAX)

select @StringConc = COALESCE(@StringConc + ',', '') + d.designation  from designation d

print @StringConc

select @StringConc as [stringOutPut]