This report documents the program and the outcomes of Dagstuhl Seminar 13021 "Symbolic Methods in Testing". The aim of the seminar was to bring together leading researchers of this field; the seminary ended up with 38 participants from 10 countries: France, The Netherlands, The Unites States, Germany, Switzerland, United Kingdom, Brazil, Norway, Estonia and Italy. Through a series of presentations, discussions, and working group meetings, the seminar attempted to get a coherent picture of the field, which transcends the borders of applications and disciplines, of existing approaches and problems in formal testing. The seminar brought together, on the one hand, researchers from the different camps and various tools. The main outcome of the seminar is the exchange of information between different groups and the discussion of new trends (parallelization, cloud-computing)