National firm Wansbroughs Willey Hargrave has been dropped from the DSS panel of legal advisers after three years.
The firm has been replaced by Simmons & Simmons and Eversheds.
The panel advises on all legal requirements regarding IT contracting, outsourcing, Public and Private Partnership (PPP), Private Finance Initiative (PFI) and contracts for non-IT goods and services.
London firm Bird & Bird has been reappointed to the board on which it has served since 1994, together with Dibb Lupton Alsop.
Peter Lee, head of Wansbroughs' PFI group, says: "We didn't satisfy the criteria it had set, but we have learnt from the experience in that we may have misjudged areas of the criteria.
"We continue to advise the DSS on ongoing projects, and we will be ready on the starting blocks next time to get back on again. We are not sulking."
Joint head of Bird & Bird's IT group Hamish Sandison is delighted: "We are very proud of our long association with the DSS as one of its IT law firms, and this reappointment will allow us to strengthen and widen that relationship in the IT field and beyond."