Great technologies, programming languages and tools are used when building software. That is good and right. But unfortunately, it is often lost sight of the fact that the decisive factor is not the technology, but the *business domain*. If we do not map the domain language and the business processes in the software, then it will not help our users in their work. No technology in the world can protect us from this. In this talk, I'll show you how you can identify problems in an existing legacy system that could be solved with Domain-Driven Design. We will see problems such as: large entities that are used all over the system, how we could divide them into smaller entities according to the business domain and how we should cut the source code into bounded contexts. All this will be done with many examples from analysis tools that help us to see the system on the level above the source code.