Reproduction is essential to the evolutionary persistence of all life. Failure to reproduce, or producing offspring that are unlikely to survive to reproduce themselves, increases the risk that the genetic legacy an individual carries will be consigned to the evolutionary scrap heap. Given these life or death stakes, it is unsurprising that organisms have developed an astonishing array of approaches to increase their reproductive success across their lifetime, find and identify appropriate mates, and ensure they have a competitive advantage when they have mating opportunities. In fishes, the focus of much of my research, the solutions employed to address these challenges span sex-change, pre- and post-mating mate choice, and a range of reproductive strategies and tactics. Here, I will highlight work from my lab that is revealing the genetic underpinnings of sex change in fish, cover work that ultimately identified a new form of post-mating sexual selection, and finish up with some new insights on the genetic, epigenetic and environmental factors that influence sperm function and male reproductive success.