Sheehan will follow former transport secretary Alistair Darling to the DTI. He will join as Darling’s press secretary, reporting to head of news Aileen Boughen.
Darling was transport secretary until 5 May, and Sheehan had been his press secretary since the position was created six months previously. He reported to head of news Marcus DeVille.
At the DTI, Sheehan will replace Bron Madson, who left last month to join the Department for Education and Skills as chief press officer, reporting to head of news John Shield.
Secretary of State for Education and Skills Alan Johnson MP does not have a sole personal press secretary, but divides spokesperson responsibilities between a team of five press officers, of which Madson is now one.
Since the May reshuffle, Alexander has pledged more cash for councils to set up congestion-charging programmes in cities such as Manchester and Birmingham, similar to the scheme operating in London.