Shapers at Odds: Isolation, Synthesis, and Resulting Division in the Assessment and Treatment of Problem Behavior

Fahmie et al. (2025) wrote a position paper. They looked at the long fight between two FA camps. One camp uses isolated contingencies. The other mixes, or synthesizes, several reinforcers at once.

The authors say the fight is hurting kids. They call for open talk instead of more turf wars.

The paper finds no winner in the isolated-versus-synthesized debate. Both sides have good data. Both sides also have gaps.

The field stays split. Clinicians stick to one camp. The split slows down good care.

Slaton et al. (2018) mapped every synthesized FA study before 2018. Their map shows the same split Fahmie wants to heal. The review gives the field a shared picture to start from.

Tiger et al. (2021) tested the two camps head-to-head in one experiment. They found both isolated and mixed contingencies can give valid data. This direct test backs Fahmie’s call to stop picking sides.

Perez et al. (2015) offered a four-phase FA that moves from brief to complex. The phased plan is one concrete bridge the camps could adopt together.

You no longer need to swear by one FA style. Read both camps, mix tools, and judge by client outcome. Start team meetings with the question, ‘What function helps this child right now?’ Then pick isolated, synthesized, or phased steps based on data, not loyalty.