Workers in the Amicus union at Selex-SAS (formerly BAE Systems) in Luton have won a union recognition agreement covering 400 engineers.
The agreement includes provisions for national bargaining on salaries with the Edinburgh and Basildon sites.
The company has previously resisted attempts by Amicus to organise the site. Most engineers at the site are post graduates and considered by the company to be beyond trade union organisation.
But management attempts to introduce new draconian contracts two and a half years ago heralded the beginning of an organising drive.
Amicus members led a successful campaign to reject the contracts and improve terms and conditions. Subsequent campaigns against redundancies and unsafe working practices resulted in union membership increasing by 200 percent.
The company has resisted collective bargaining but the intervention of Amicus, growing membership and the prospect of a union campaign to win a ballot forced its hand.