Build for the rotation, not for one cat
A foster household that takes a new rescue cat every few months cannot rely on knowing the individual at the door. One foster may hide from the bell for a week; the next may be a confident door-darter who was surrendered precisely because he kept escaping. The proofing therefore has to be structural and permanent — part of how the house works, not a set of tricks tuned to a single animal. Treat every new arrival as a capable escape artist for at least the first fortnight, and relax only on evidence from that cat, observed over calm weeks, never on hope.
Give every foster the same safe starting room
Set up one room, away from the front door, as the standing foster room: litter box, water, scratching post, hiding box, and a door that closes and latches properly. New rescues start there anyway while they decompress and are assessed, which means during their riskiest, most unsettled days they are automatically behind a closed door when deliveries arrive. As a foster earns more of the house, keep the delivery rule unchanged — back into the foster room, door shut, then the front door opens. Test that room's window latches and any shared doorway each time a new cat arrives, because a previous foster may have loosened a catch you have not checked since.
Make the entryway itself a permanent airlock
Where the layout allows, keep an inner hall door or a fixed gate always in play, so there are two closed barriers between any cat and the street at delivery time. Put the standing sign on the front door once — foster cats in residence, parcels to the step please — and add delivery instructions to your regular shopping accounts so the message does not depend on a new driver reading carefully. Keep the porch routine identical for every foster: no propped doors for big boxes, no signing on the threshold with the door wide, and no exceptions for neighbours' parcels taken in as a favour, which are the deliveries foster carers most often forget to proof for.
Log each cat's door behaviour for the next home
Foster care gives you information an adopter desperately needs: does this cat charge doors, freeze and hide, or ignore openings entirely? Note it after every delivery week, along with what worked — a particular room, a feeder toy that held her attention, a gate height she tested. That record protects the cat twice: it sharpens your own routine for her remaining stay, and it lets her adopter set up correctly from day one instead of learning about a door habit the hard way in an unfamiliar street.
When a foster cat does get out
Act fast and use the rescue network you already have: the organisation you foster for will usually help with traps, posters, and local volunteers, and a foster cat's microchip and description should already be documented with them. Search the immediate hiding spots first, since a cat in a strange area usually goes to ground close by, and keep the foster room's door and scent items ready for her return. Tell the rescue the same day, even if she comes home by evening — they need the incident in her record. KinsLe's Transferrable Profiles let a foster cat's profile pass to her adopter with history, records, and routines intact, so the escape notes and door routine you built follow her into her permanent home.