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The breeding biology of the North Island Tomtit (Petroica macrocephala toitoi) was studied at two sites in Pureora Forest Park, central North Island, during the 1997/98 season, and compared with data from the Ornithological Society of New Zealand’s Nest Record Scheme. The nesting season at Pureora was from 26 September 1997 to 15-17 February 1998, one pair fledging three broods. Of 11 Pureora nests and 32 of the Nest Record Scheme, 63.6% and 28.1% respectively were among dead hanging fronds of tree ferns, and 18.2% and 34.5% respectively were in holes in trees, rocks, banks, the ground or in nest boxes. The mean height of 11 nests at Pureora was 3.4 m, and that of 34 nests in the Nest Record Scheme was 2.8 m. Mean clutch size for the combined data was 4.15 eggs (n= 13). On all occasions, except one, females were incubating, with males feeding their mates at regular intervals. Both parents fed the chicks but only the female brooded them. Mean brood size at Pureora was 4.0 (n=4), but for the Nest Record card data it was 3.1 (n= 2 1). All 13 fledglings in four broods appeared to reach independence. Of 11 nesting attempts at Pureora, 72.7% were successful, compared with 45.4% of 11 attempts on Nest Record cards. This greater success at Pureora compared with other mainland areas was attributed to aerial 1080 possum control at Pureora reducing mammalian predator densities to low levels, and so reducing the incidence of predation.