This book constitutes the proceedings of the 22nd Nordic Conference on Secure IT Systems, held in Tartu, Estonia, in November 2017. The 18 full papers presented were carefully reviewed and selected from 42 submissions. The papers address a broad range of topics in IT security and privacy. They are organized in the following topical sections: outsourcing computations; privacy preservation; security and privacy in machine learning; applications; access control; and emerging security areas.