The main purpose of the thesis is to introduce a method for data migration quality assurance or completeness and accuracy testing of migrated data. Method will become part of the knowledge base of Deloitte Czech Republic for projects in the Enterprise Risk Services department. Data migration quality assurance projects carried by Deloitte in the Czech Republic have its own specifics. Although there exists methodology "Systems Development Playbook" which also includes a data migration methodology, the problem especially of the Prague branch is the fact that the procedures and methods for consulting projects in the area of data migration are not described in current methodological documentations including specifics of the Czech and Slovak projects. This represents a risk of inconsistencies in the implementation of this type of consulting projects in case of key employees leaving. Improving procedures and optimization of human resources engagement in data migration projects can't be measurably compared among projects, if there don't exists a basic methodology against which specific projects can be measured. The objectives of the work are achieved by consolidating experience from past projects involving data migration within Deloitte Czech Republic and designing improvement of existing processes by integrating information from external sources and internal sources of the global Deloitte Touche Tohmatsu.