Аннотация:The binding of donor‐acceptor Stenhouse adducts (DASAs) bearing hydrogen‐bond recognition groups by Hamilton ‑ type receptors significantly influenced their photoswitching properties by altering thermal barriers to isomerization. The thermal barrier between the most stable linear isomer and the photo ‑ generated isomer is lowered on binding to a receptor, and this barrier is crucial for switching properties. The thermal isomerization was shown to proceed via a stepwise linear‐ enol ‐ keto mechanism in DMSO where the tautomerisation barrier is within 2 kJ·mol ‐1 of that of the rate‐determining step, which may be important for analyzing switching properties.