I’m going to go off on a little rant here. It’s a bit of a continuation of what’s on our home page, but I think it needs to be further explored.
When I first started SSM in ’99, I kind of went with the shotgun theory of “I’d like to be able to provide every service possible to every customer” so that I wouldn’t lose any business. Throughout the years we’ve been able to keep the majority of our customers happy, partly because we realized that if you’re trying to do everything then you’re going to succeed at nothing. It’s pretty common throughout the universe. We’ve all heard the descriptor, “Jack of all trades, master of none”. 
Wouldn’t it be a whole lot smarter to be the master of a few things, know what they are and then find the people who are the masters in the areas that you need help with? Seems like simple logic to me.
Yet a lot of the marketing material that I see for our peers still says, “one stop shop”. Really? Are you offering doughnuts and oil changes too?! I don’t want an application built by someone who also offers hypnosis. I don’t want my marketing put together by someone who will also fix a flat tire. I want them to be sure that they know whether WordPress is the solution or if Drupal or Joomla are better options (which they aren’t, FYI). I want them to be able to foresee issues that might arise that I’m not thinking of just because it’s not my job to know, it’s theirs.
You wouldn’t go to a lawyer that also sold bait. Why would you go to an application developer that also purports to be an expert at language translation. Or an ad agency that also wants to do virus scans for your PC?
Know what you know and know what you don’t and then be clear about it. One stop shop sounds really good, but in the end it just ends up as two different kinds of java.