Yobesh Amoro and David Musau Mbithi, who worked in the east African office of the charity, walked free after the verdict in Nairobi. Police and prosecutors in Kenya are waiting for details of the judgement before deciding whether to take any further action.
Practical Action said it was disappointed at the outcome. Simon Trace, the charity's chief executive, said: "We will not allow this or any other setback to stop us focusing on what is important - and that is delivering our work to those who need it most."
A forensic audit carried out by consultancy PriceWaterhouseCoopers revealed that Practical Action, then known as the Intermediate Technology Development Group, was the victim of a "sophisticated fraud", estimated at £1.5m, between 2000 and 2003 (Third Sector, 16 August).
It is believed to be one of the biggest frauds perpetrated on a UK international NGO. However, the court case concerned the loss of only £300,000.
"NGOs face challenges on a daily basis," added Trace. "We have worked with fragile communities in difficult circumstances for many years and will continue to do so in the future."