10/13/2026
Three studies, and then the hole where a fourth should be.
Weiss and Gramann compared 78 cat adopters who paid a $75 fee against 95 who paid nothing, then measured attachment. No difference. Both groups equally attached, both equally positive about the shelter they adopted from.
Weiss and colleagues compared traditional screening, landlord checks and required dog-to-dog introductions, against a staff conversation. 96 percent of the animals were still home at follow-up and there was no difference in retention between the groups. The authors wrote that policy-based approaches could be wasting effort.
Powell and colleagues analyzed 23,932 adoptions at Charleston Animal Society over five years. 9.2 percent came back within six months. For dogs, 16.3 percent.
So the fee does not decide it. The application does not decide it. And one dog in six comes back anyway.
Which leaves the question of what happens in between. Here is what I found when I went looking.
Best Friends published a literature review on adoptions last year. It covers fees, open adoption, deliberation time, breed labels, photographs. On post-adoption support and whether it changes retention, it has no findings. The most serious attempt I can find anywhere is the Dogs Trust cohort, 5,498 adopters across 20 centres with scripted calls at two days, two weeks and four months. The paper describing it came out this year and it is a methods paper. The evaluation is still to come.
There is a second problem underneath that one. The open adoption study measured at 30 days. Powell measured at six months. Those windows are practical, not evidentiary. A lease renewal with a new weight limit. A vet bill in month eleven. Resource guarding that starts when the kids go back to school. None of those are 30-day events.
I run a post-adoption program. I do not have evidence it works. Nobody does, for any version of it, which is the whole point. I am not going to spend two months writing about numbers nobody sourced and then imply my own are proven.
And waived-fee events are capacity management, which is a real job they do well. The research says those adopters are fine. The problem is what happens when a pressure valve gets reported as an outcome.
If I have missed a study, tell me. That is the best possible response to this post.
Full piece: shift.animal-angelsfoundation.org