Feeding resulted in immediate upward shifts of between 0.62 and 3.00 K in the mean set points at which basking started and ceased (Tbask and Tmove) in P. muralis allowed to thermoregulate beneath tungsten bulbs giving three different levels of radiant heat, except for Tmove in lizards at the highest level (70 mW cm-2 measured in the range 8 000-14 000 nm). Mean bask durations decreased following feeding, but mean forage durations also decreased and the overall times spent basking increased. Values for all four variables declined gradually, returning to pre-feeding levels after 30-50 min. Feeding had no effect on mean heating rates. Feeding in Lacerta vivipara also resulted in increases in set point temperatures, but mean bask durations increased following feeding in this species.