The annual account - which has fees of more than £300,000 - was won after a competitive pitch.
NEC UK central marketing manager Karen Tipping, to whom the agency reports, said Nelson Bostock had been hired to raise NEC's profile and 'better communicate what we do'.
The account sees Nelson Bostock handling PR for five NEC divisions: 3G systems, cellular, data storage, plasma and network systems.
The agency is to launch a major PR push around the 3G business, with B2B and consumer work set to coincide with the rollout of 3G services.
NEC provides infrastructure and equipment for 3G mobile networks. Its handsets and infrastructure services are among those being used by Hutchison 3G in its ongoing technology trials.
Nelson Bostock will seek to promote NEC within the mobile industry, before expanding the focus of the campaign to target other audiences.
Attenborough Associates continues to retain the PR remit for NEC's data projectors, an account it has held for two years. Media relations and exhibition work for this division is mainly in the B2B and education sectors.
The pitch for the business won by Nelson Bostock was held 18 months ago, but the hiring of the agency was put on hold after a decision by NEC to restructure its six-strong marcoms team.
With the restructure - which meant the centralisation of each division's marcoms teams - completed and now 'bedded in', Nelson Bostock has now been hired, said Tipping.
A seven-strong Nelson Bostock team is working on the account.