As part of a radiotelemetric study of echidnas (Tachyglossus aculeatus) in south-east Queensland focussing on thermal relations, we were able to confirm and extend present knowledge of echidna reproduction. Mating was concentrated in July and August, as elsewhere, but we found that echidnas have the ability to conceive successfully a second time within the one season, apparently in response to losing the first young. Echidnas in this area of south-east Queensland may be able to attempt breeding every year. Our data supports published estimates of gestation in the range of 20 to 23 days. Females spent two to three weeks in a plugged 'incubation' burrow, maintaining a high and stable body temperature for a period encompassing the last few days of gestation, all of incubation and the first few days of the hatchling's life. The single young was carried in the female's pouch for 45-50 days, attaining a body weight of approximately 200g before being stowed in a different plugged 'nursery' burrow. We describe the first detailed timing of a female's visits to suckle her young. She visited regularly, every six days at first, gradually increasing in frequency to about every four days before the visits ceased and, presumably, the newly-independent young emerged at a calculated five and a half months of age.