Event Sourcing might appear easy and straight forward at a first glance. However there are some tough challenges to address in real world projects: "What about parallel updates?", "Where should I validate my data?", "How about consistency?" There isn't an easy catch-all answer to these questions.This talks addresses exactly these demanding challenges and offers ideas and possible solutions for them. In addition to that you will be able to consider advantages and downsides in discussions surrounding advanced Event Sourcing challenges.