Artificial insemination (AI) is a key driver of genetic gain in the wool industry as it facilitates the widespread dissemination of genes from superior sires. The degree to which artificial insemination can influence the genetic gain of a flock is linked to the success of that program, namely the pregnancy rate achieved. Sub or infertility of individual sires or batches of semen is a signficant factor in reduced pregnancy rates to AI and is a discouragement for broader uptake of the technology. This project aims to identify in vitro predictors of sperm fertility using an array of advanced semen assessment techniques to test semen destined for AI, with correlations made to pregnancy outcome. As a result, new standards for the testing of semen prior to production and sale will be developed and recommended to industry.