Working in custom software development as a tester, I often could not find contact and a common language with the analyst. But then, by coincidence, I started working as an analyst myself, which allowed me to look at the problem of interaction from a different angle. How can an analyst help a tester at different stages of a project? What does the tester expect from the analyst, what cases can he be interested in? The talk will be of interest to those who want to understand the testing and establish more effective teamwork.