Maso's start date was July 19.
Maso was the mayor of Frisco for nine years and was term limited this year. He is also a former member of the Frisco Economic Development Corp. board of directors.
As mayor, Maso said he saw Frisco and Prosper partner on a number of key issues in the past, and he sees the two cities helping each other with economic development.
"Frisco and Prosper have partnered on water issues, on technology issues, roadways, and those aren't always on the forefront where everybody gets to see them," he said. "But the reality is all of us depend on each other."
As of Jan. 1, Prosper's population was about 20,000 people, which is about 140,000 fewer people than Frisco. The town's annual growth rate is higher than Frisco's at 13 percent. Prosper's land area is 27 square miles, whereas Frisco's is 68 square miles.
Maso said Prosper's strengths are similar to Frisco's strengths: a well-educated workforce, a great master plan, a strong educational system and established infrastructure.
Maso said he has a lot of established relationships in Frisco that are not going away, and he wants to see both cities succeed.
"The better Prosper does, the better Frisco does. And the better Frisco does, the better Prosper will do," Maso said. "Those things are related and interlinked. It's not one or the other; it's one and the other."