Woodcock began his heraldic career in 1975 as a research assistant to Sir Anthony Wagner, Garter King of Arms.

[4] In 1982 he was promoted to Somerset Herald,[5] becoming Norroy and Ulster in 1997,[6] then Garter Principal King of Arms on 1 April 2010.

[7] On 1 July 2021, Woodcock retired as Garter as well as his other heraldic and genealogical offices.

[9] Woodcock was appointed Lieutenant of the Royal Victorian Order (LVO) in the 1996 Birthday Honours,[10] promoted Commander of the Royal Victorian Order (CVO) in the 2011 Birthday Honours[11] and Knight Commander of the Royal Victorian Order (KCVO) in the 2021 Birthday Honours.

[12] In 2017, he succeeded William Hunt, Windsor Herald, as Genealogist of the Most Venerable Order of the Hospital of Saint John of Jerusalem serving until 2021,[13] having been appointed in July 2018 an Officer of the Order (OStJ).