Definition
An automated series of messages (email, text, sometimes a scheduled call task) designed to move a lead from first interest toward a decision over days or weeks. Usually triggered by a capture event like a form fill or missed call, with each step timed and conditional on what the lead has done.
What it looks like in practice
At eleven at night, a personal injury firm gets a form fill. The sequence starts immediately: a text confirming a real person will call in the morning, plus an email explaining what happens in a first consultation. Next morning, a call task lands on an intake coordinator's list. If the call connects and a consult is booked, the sequence stops there. If it does not, day two sends a short answer to the question most callers ask; whether there is a deadline to file, and day five sends a case result. After day twelve the lead moves to a monthly newsletter instead of another chase.
Why it matters
Most people who inquire are not ready to buy that day, and without a sequence they drift to whoever stays in front of them longest. The design detail that matters is the exit condition: a sequence that keeps sending after someone has already booked, or after they have said no, does more damage than not having one. Good sequences branch on behavior (replied, booked, went quiet) and stop cleanly. Tone is the other tradeoff. Messages that only push for a decision start reading as spam by the third one, so each step should be worth opening on its own, not just another nudge.