In order to prepare for a greater penetration of renewable generation in the Irish market, the incumbent TSOs set up a programme called “Delivering a Secure Sustainable Electricity System” (DS3) to ensure that the market and transmission network is able to accommodate these changes. In particular, this has impacts upon the needs for ancillary services and the way in which they are procured. ESP Consulting was engaged with the two Irish Regulatory Authorities in the development of associated policy design, with activities including: