JIM, "minimal" means direction, purification of water and fire. Anything else you can get in is a bonus. I have a tin like this. It's 3" x 3" x 1". Small enough to fit in a pocket and forget about, but big enough to hold a worthwhile amount of kit.

I work on the basis of being able to purify 3 liters of water, start 2 fires and know which direction home is. If thing go totally pear shaped then anything else I need is going to be foraged.
Which is comparatively easy in an urban enviroment.