John Booth says that Manor Marussia is entering a 'positive phase' after a difficult start to the 2015 season.
Booth's squad endured a turbulent winter period as it fought for survival before making it to the first race of the year in Australia and returning to the grid in Malaysia.
Despite occupying last place in the Constructors' championship, Booth says that the situation is improving and that the outfit should be back to full strength by the end of the year.
"After a very difficult, well-publicised start to the season, we are at last entering a positive phase," said Booth.
"[At the] last couple of races we have brought on board a couple of multi-national companies that are new to Formula 1.
"We are back in the windtunnel on a regular basis, [we] started last week, and we brought the updates to the race [at Silverstone]. But on first year looking very positive and we want to continue in that vein and keep pushing forward.
"We started in Australia with really a skeleton crew in Silverstone at the office, the full operating crew at the circuit.
"But over the months we've been gradually building the staff base back at the office and we hope by the end of the season we will be back up to full strength."