Stored Procedures under Source Control, best practice

Question

I am currently using Tortoise SVN to source control a .NET Web Application. What would be the best way to bring our SQL Server stored procedures into Source Control? I am currently using VS 2010 as my development environment and connecting to an off-premise SQL Server 2008 R2 database using SQL Server Data Tools (SSDT).

What I have been doing in the past is saving the procs to a .sql file and keeping this files under source control. I'm sure there must be a more efficient way than this? Is there an extension I can install on VS2010, SSDT or even SQL Server on the production machine?