Backpack, Vest, or Both?

When it comes to taking gear out into the field, what is the most effective way of organizing it? Personally I like tactical type vests because everything is much more accessible and the weight is more evenly distributed. But with a backpack you tend to have more space to put things, and it's easier to get on and off. I do know that some people use the vest approach, but have a removable backpack on it as well. So, do you prefer a vest, a backpack, or both to haul your gear in the field?

I prefer back packs to vests for the most part. They tend to be cheaper, easier to use, more space, and more options. I find vests tend to get hot and you need to get all the pouches for everything and then attach them. Vests do seem to distribute the weight better, and are very customizable, but if you fit your pack correctly they can be fairly comfortable with out wrapping yourself in thick layer. I will say though, if I only have a small load, say a day pack for hiking, I prefer to use a battle belt set up. The belt evenly distributes the weight on my hips while allowing airflow around my torso. The belt also allows for customization and it's easier to put on and take off the pouches than it is on a vest.

Those are some good points. The battle belt is a good mid-point, and if it's heavy you also have the option of adding suspenders. For me I think each thing serves a different purpose, so it really depends on the mission.