Piglet survival is a problem of great significance in pig production, affecting both animal welfare and economic aspects negatively. In Sweden it is illegal to use farrowing crates for sows on regular basis. To encounter this problem there is a proposal of an animal welfare program to allow the use of crates for sows during, and a number of days after, farrowing. The proposal aims to reduce piglet mortality and improve pig welfare. This present review aims to analyse how crating affects the welfare of sows, gilts and piglets as well as piglet mortality.