Lump-sum turnkey (LSTK)

LSTK stacks the two strongest transfers in contracting: the lump sum moves cost risk, the turnkey obligation moves completion risk. The contractor's promise is not effort but an outcome — a facility that, at handover, passes its performance tests and runs. The commercial machinery matches the promise: performance guarantees on capacity, efficiency and product quality; liquidated damages for delay and for performance shortfalls; payment tied to milestones and, at the end, to demonstrated performance rather than assembled hardware.

The model is the standard vehicle for process plants and power projects, and for lender-financed ventures generally, because it produces the thing financiers can underwrite: a price, a date, and a warranted output, all with one throat to choke.

Its honest price is the premium on all that certainty, and its honest limits are the owner obligations that survive it — feedstock, utilities, permits, decisions, access. "Turnkey" describes the handover, not the owner's project role, and owners who read it as permission to disengage rediscover the distinction in the claims register. The other quiet term worth reading twice: what the performance LDs actually buy out, and what happens when their cap is reached.