Bns Telecom Group staff are keeping watch on the progress of their new £2.5m headquarters in Northumberland - through a camera linked into the company's website.
The 22,790sq ft building next to Prudhoe railway station will be completed in August and accommodate up to 300 workers.
The existing HQ staff have been holed up in 7,500sq ft of temporary office space next to the new development for the last two years.
Managing director Garry Moat said: "Starting work on our new HQ marks the latest stage in the company's development."
The company, one of the UK's largest independent telecommunications services providers, handles millions of calls a month for more than 10,000 UK companies and has seen an eight-fold increase in turnover to more than £20m in four years.
Mr Moat said: "We moved into our present offices just over two years ago, but swiftly outgrew them, so we needed our additional temporary offices to give us the breathing space we needed to keep growing until our new premises became available."
The business raised £8m from a stock market flotation last year. Mr Moat believes the start of construction work on the new building is a milestone for the AIM-listed outfit.