Gilbert joined the British Civil Service as an assistant principal, in the Ministry of Health in 1949. He was promoted as follows: Assistant Private Secretary: to Minister of Housing and Local Government, 1952; Parliamentary Secretary, 1954; Principal, 1955; Secretary to the
Parker Morris Committee on Housing Standards, 1958–61, Rapporteur to ECE Housing Committee, 1959–61; Reporter to
ILO Conference on Workers’ Housing, 1960; Assistant Secretary to the
Local Government Finance Division, 1964; Under-Secretary, Department of the Environment, 1970–80 (for New Towns, 1970, Business Rents, 1973, Construction Industries, 1974, Housing, 1974, Planning Land Use, 1977); Deputy Director, 1980–81, Director (Deputy Secretary grade), 1981–86, Department for National Savings. In 1980, Chancellor Geoffrey Howe had decided that National Savings should fund a substantial part of the
Public Sector Borrowing Requirement (PSBR), and for the first time in its history, National Savings was given a specific target (£2Bn), and under Gilbert's leadership it met that target, and subsequent targets for 1981-82 (£3.5Bn target), and for 1982-3 (£3Bn target). In August 1983, Gilbert commented: "It's easier to run an organisation which has a clear objective". Gilbert further commented that the Department had a "close and informal relationship" with the Treasury. In 1983-84 the Department's target was again £3Bn, which at that time was about one third of PSBR. In August 1982, Income Bonds were launched for the first time, and by the end of the financial year they had taken £891 million, after National Savings' own research suggested that there was a low awareness among the investing public of monthly income accounts. Gilbert noted that: "We don't have as large a research capacity as some institutions seem to have, but we're increasingly hoping to use outside organisations". On 2 August 1986, Mr J.A. Patterson succeeded Gilbert, who had previously been his deputy, as Director of Savings at National Savings. == In retirement ==