Imagine that each circle in the diagram represents a stack of liquid fuel tanks with a standard Liquid Engine at the bottom (Perhaps use a vectored thrust center engine for better control). The outer stacks are attached to the central stack by radial decouplers (not shown) and the yellow arrows are fuel lines. The No Crossfeeding example is a basic setup. The six outer engines burn as S2, and then are dropped. The inner engine then ignites on a full rocket, and starts burning. The Crossfeeding example runs fuel lines from the bottom tank of the outer ring to the bottom tank of the inner engine. All seven engines start burning on launch, and the inner engine is getting all its fuel from the outer tanks. This setup provides higher thrust off the pad than the No Crossfeeding example, but delta-V works out to be the same. However, because the atmosphere is thickest at the surface of Kerbin, it can provide better overall performance by getting out of the lower atmosphere quicker. Asparagus Stalk Booster Staging is a subset of Crossfeeding , where again, all seven engines ignite on launch. However, instead of dropping the outer ring all at once, fuel lines and staging are set up so that all the fuel drains from the S4 tanks, and those are dropped, followed by fuel draining from the S3 tanks, and dropping them, followed by draining from the S2 tanks and dropping them, and finally burning the S1 fuel. Asparagus Staging combines the high thrust on launch advantage with an efficient mode of dumping empty tanks while keeping the rocket balanced. It provides a somewhat significant boost in delta-V over regular crossfeeding. Three-tank-high Asparagus Staging is what I use in my standard stock Munlanders, and for a variety of other pursposes. It is a bit of overkill for a Munlander, to be honest; I often find myself chucking mostly-full boosters at the Mun to get them out of the way of the lander. Standard crossfeed does increase delta v because it sheds the outer tanks slightly earlier than no crossfeeding.