Abstract This presentation has been written for those who may be considering practical intensification of sheep production and need information about its implications, potential and hazards, as well as for those with interests in this field of research. The limited literature on sheep housing and the management of a housed flock are considered, together with the importance of prolificacy and the suitability of a number of South African breeds to accelerated lambing. The productivity of a housed Ile de France flock in which three lambings a year was an objective, and difficulties met during 14 years of the flock's existence, are presented. 'Effective teaser rams' (ETRs) that both induce oestrus and increase lambing rate by as much as 20% have been noted and it is suggested that these as well as vasectomized goats (Effective teaser goats (ETGs)) may profitably be used for these purposes.