I don't usually do a chapter by chapter outline, but a timeline of what I want to happen and just write from there. I find that it works for me, especially with Running Up That Hill since that story is so dependant on when things happen right down to the day. This way I have some wiggle room if my imagination decides to come up with something new on the fly, but I also have the loose outline/plan of how I want to get my characters where they are going.
