Have you ever used an inbetween person for dealing with clients? Maybe you’re a freelancer that hired a project manager to deal with clients? Or maybe you felt communication with a big client was over your head and hired a pro to get the deal done? I’m interested to hear from your experience 
I am a 19 year old designer who just finished up his first year in university. In High School, however, I was very involved in my digital media program and I began freelancing there about two years ago. I became such good friends with my old web teachers that they now outsource work to me. A large majority of my projects come from this and personally I love it. I know and trust these people and, as Shyflower said, I only get one set of directions. Plus, if the client gets heated, I’m not really the one who has to deal with it!
Actually, I’m in the process of going through something like that, ironic you should bring it up! Because I’m looking for additional clients to “top-up” my my web consulting side of my business what I’m doing is approaching other business owners to act as a sort of intermediary middle-man myself. Seems rather strange I know but the idea is that if I attach myself to existing web design businesses they can pass on their stuff when it’s produced and I can do audits and reports on the things I know most about (like accessibility, usability and UX design) which many designers don’t have the time or knowledge to undertake. Thereby I don’t need to complete with the huge amount of agencies in my region and I get the benefit of working with other established professionals and they get the benefit of outsourcing the theoretical applied web design subjects to me (an independent body) to ensure they keep their standards up thereby improving their own business. 
PS: I had the idea to go in this direction off the back of my article writing as I’m literally outsourcing my skills to places where they would be useful.
Whenever possible, I prefer to do outsourced work through my client’s project management. That way I only get one set of directions or suggestions from the person who is paying me. I also make sure that my client is included (“CC”) in all email communications and send them notes on phone conversations.
Keeping things well-documented keeps both projects and client-provider relationships on a smooth and level plane.