The effects of swine gestation housing on sow and litter performance were evaluated at the Iowa State University Lauren Christian Swine Research and Demonstration Farm near Atlantic, IA. The gestation systems were 1) individual gestation crates in a mechanically-ventilated, partially-slatted floor manure flush confinement building (CRATE); and 2) group pens in deep-bedded, naturally-ventilated hoop structures (HOOP). The HOOP sows were fed in individual feeding stalls. The sow genotypes were 1/4 Hampshire × 1/2 Yorkshire × 1/4 Landrace. Farrowing occurred every 2 weeks throughout the year.