Agree at the start of a meeting what it is for, both agendas, the time, and the three acceptable endings: yes, no, or a dated next step. Say out loud that no is fine.
The meeting ended with "let us think about it", and you have been waiting ever since.
Agree how the meeting will end before it starts. At the top of the meeting, both sides say what it is for, what each wants out of it, how long it runs, and which endings count: yes, no, or a next meeting with a date and a purpose. Say out loud that no is a fine answer. Ruling those three in rules "we'll think it over" out, and you ask for the agreement while the buyer can still object to it.
Sandler Training calls this the up-front contract.
Mike Crandall's five parts, on Sandler's site. The purpose of the meeting; the other person's agenda and expectations; your agenda and expectations; the time and logistics; and the outcome, the clear next step both sides leave with. His sample script for an insurance agent thanks the buyer for their time, says both sides will have questions, frames the conversation as deciding whether they are a good fit, says it is fine to say no and that no decision has to be made on the spot, and ends by asking whether all of that is all right.
David Fischer's three endings, also on Sandler's site. The only acceptable outcomes of a call are yes, the prospect moves forward; no, it is not the right fit; or a defined next meeting with a clear purpose. His openers ask how much time the prospect has set aside and what they see as the main purpose of the call, then say the seller will need to ask about budget and implementation if there is a fit, and ask whether that is acceptable.
The source book. The method comes from David Sandler and David Mattson's You Can't Teach a Kid to Ride a Bike at a Seminar.
Nobody has measured it. No study compares sellers who open meetings with an up-front contract with sellers who do not, and Sandler, which teaches the move and sells the training, publishes method rather than data. Gong's data on discussing next steps in the first meeting, the only measured thing near the last element, is under Earn the next step before you book it.
Telling people they are free to refuse. In Nicolas Guéguen and Alexandre Pascual's 2000 street experiment, 10% of strangers gave bus money when asked plainly and 47.5% when the request added "But you are free to accept or to refuse." Adrien Fillon and colleagues' pre-registered review in Meta-Psychology, co-written with Pascual, pooled 52 experiments and 19,528 people and found a moderate effect overall, stronger face to face. But in the seven studies rated at low risk of bias, the effect was small and not distinguishable from zero. The permission line may help; the best-run studies cannot show that it does.
The word you use to ask what else they want. The second part of the contract asks for the buyer's agenda. John Heritage and colleagues' trial with 20 family doctors found that asking for further concerns with the word "something" cut patients' unspoken concerns by about three quarters, while the same question with "anything" did no better than not asking. The full trial is under Schedule the concerns conversation before the close.
Warning people that a pitch is coming. Wendy Wood and Jeffrey Quinn's two reviews in Psychological Bulletin found that people told a persuasion attempt was coming leaned towards the coming view beforehand, then resisted once it arrived, most of all on topics that mattered to them. An up-front contract announces that the seller will ask for a decision, so it carries that cost.
None of this evidence involves a buyer or a purchase: it comes from strangers asked for coins, patients in a consulting room and students rating opinions. Nobody has compared a team that contracts every meeting with the same team that does not. The move rests on its parts, and the best-run studies of the permission line find it close to nothing.
Before the meeting gets going, agree the purpose, both agendas, the time and the three endings you will accept, and say out loud that no is one of them. Ask for their agenda with "something", not "anything". Treat the move as a way to get a clear answer; no study shows it wins more deals.