The most effective basis for derivation of simple feeding rules to ensure sow productivity is still in question. Liveweight change has emerged from a long series of feeding experiments as being potentially adequate for the purpose, however this has not net with success in pig units in the face of unwillingness by commercial sow herd managers to regularly weigh their sows. The most likely contender as an alternative to sow weight change as a measure of effective sow feeding is body condition; especially the amount of fat carried on the back. Indeed, it may be that body condition is a better indicator than live weight of the propensity of a sow to breed. It is possible to envisage recommended guidelines for feed allowances based upon condition score, or, more objectively, from a simple ultrasonic measurement of backfat depth at P2. The immediate objective of the current experimentation was to arrive at simple statements of targets for condition score and backfat depths which might be indicative of adequate and cost-effective sow feeding.