This article maps the challenges faced by European trade unions arising from the growth and diversification of employment in private sector services, and analyses union responses to these challenges. Focusing on recruitment, internal interest intermediation, and articulation between the central and local tiers of union activity, it shows that many unions are making considerable efforts to renew their organisational structures and policies, so as to reverse the decline in membership and strengthen their workplace presence in private sector services. Approaches include union mergers, extension of collective bargaining into new areas, development of new styles of organising, digital unions, and creation of unions for particular groups. A critical issue is how to combine the differentiation and decentralisation of unions with coordination of union objectives: union renewal is a contested process, implying difficult choices as regards target groups and internal power relations. The article suggests that although the reforms have been insufficient to turn the tide thus far, the breadth of change cautions against precipitate judgements about the demise of unionism in private sector services.