Thomas Ashe

Robert Byrne

Transwestern Partners Thomas Ashe and Robert Byrne have joined rival Cushman & Wakefield’s Boston office as executive director and managing director respectively, bolstering its downtown and suburban office leasing teams.

Monday’s announcement comes after two other Transwestern partners, Michael Joyce and Robert Richards, made the jump to Cushman & Wakefield in the past month.

Ashe joins Cushman & Wakefield’s downtown leasing group. Byrne will specialize in the south and central 128 suburban markets.

Richards, a co-founder of Richards, Barry, Joyce and Partners prior to its acquisition by Transwestern in 2013, joined Cushman & Wakefield as executive vice chairman this month. Joyce, who has represented clients including the Boston Celtics, Wilmer Hale and Brookfield Properties, was named vice chairman of Cushman & Wakefield’s downtown Boston leasing team in January.

“Tom and Rob are proven team players who have separated themselves from their peer group. Each brings positive energy and enthusiasm to their work with clients as well as to their colleagues in the office,” Carolyn Sidor, managing principal and New England market leader, said in a statement.