Open, closed, leading, and tie-down — the documented four. Each type has a job and a stage: open questions run discovery, closed questions pin down facts and confirmations, leading questions frame agreement once the facts are in, and tie-downs collect small agreements as the presentation builds toward the decision.
The short answer
Open questions invite explanation: “What made you guys decide to have someone out?” — the discovery workhorse. Closed questions get a specific answer: “Has the roof leaked before?” — facts, timelines, confirmations. Leading questions carry the answer inside them: “You'd want the installation done right the first time, right?” — agreement framing, used after discovery, never instead of it. Tie-downs are the small closing questions attached to statements as you go: “Does that make sense?” “Fair enough?” “Would that work for you guys?”
How it runs
Most question failures are type failures, not wording failures. Leading questions in discovery collect agreement and starve you of information — you leave with a pile of yeses and no idea how to sell them. Open questions at the confirmation stage invite speeches when you needed a fact. The skilled rep isn't choosing better words for one favorite type; he's matching the type to the moment — open to learn, closed to confirm, leading to frame, tie-downs to build.
The fuller question family — follow-ups, involvement questions, alternate choices, the porcupine — all grow out of these four, and each has its own guide in this section.
Go deeper
Spar's rounds grade your questions and your listening against the documented system — Round 1 is free, the full camp is $29/month. Spar before you knock.