Defensive Security like Threat Detection and Incident Response is asymmetric warfare. We have to learn something about everything, while the attackers just need to find the one path past our defenses and monitoring. Within a company, the team may be small, but elsewhere in your city is someone fighting the same battle you are against a common opponent. Joining forces with your counterparts at other companies will enable you to commiserate, learn new tools and techniques, and share insight into the shared threats. This talk will cover how to find an existing local forensics group and also how to start your own.