DX (Group) plc (trading as DX and DX Freight) is a British mail, courier and logistics company, with operations throughout the UK and Ireland.With operational hubs and head offices in Iver, Northampton, Nuneaton, Warrington, Willenhall and Dublin, DX Group has established a network covering 99.7% of UK & Ireland business and residential addresses.Established in 1975, amongst the Royal Mail postal strikes of the 1970s, DX Group had been in private ownership since 2006 and combines DX Network Services Ltd, DX Secure (previously Secure Mail Services (SMS)) and as of 15 March 2012, DX Freight, previously known as Nightfreight GB.DX employs over 3,000 people within the UK and Ireland, many of them couriers.