There is growing appreciation that management and conservation outcomes could be improved by incorporating evolutionary principles.  Here I will provide several examples to illustrate the gains made by incorporating evolutionary principles into management decisions, including examples focusing on the evolutionary and ecological impacts of harvest and aquaculture, and how to minimize those impacts. This body of work highlights the importance of considering biodiversity below the species level in management and conservation efforts. In particular, a focus on population-level variation and variation among individuals within populations (the raw material of evolution) is warranted and necessary. In fact, shifts in intraspecific diversity might serve as an early indicator of undesirable population change. While challenging, conserving or restoring intraspecific diversity within fish populations is a proactive strategy for managing for resilient populations in an era of rapid change.