The International Tennis Federation (ITF) will manage and enforce the Tennis Anti-Doping programme in women's tennis from next year.
The ITF, which organises Grand Slam tournaments, Federation Cup and the Davis Cup, joined forces with the men's ATP Tour last year.
The ITF already tests at Grand Slams, the Fed Cup and ITF women's circuit.
The Tennis Anti-Doping Programme is fully compliant with the World Anti-Doping Agency's (Wada) code.
ITF president Francesco Ricci Bitti said: "All three governing bodies, the ITF, ATP and WTA Tour, have the same objective - to protect our players and keep our sport drug free.
"The ITF believes that having the management of the entire Tennis Anti-Doping Programme under one umbrella is the most efficient and sensible way forward for tennis.
"Our agreement with the ITF sends a clear message that the governing bodies of our sport are determined to continue doing everything possible to ensure that tennis remains clean, " WTA Tour CEO Larry Scott said.
The agreement between the ITF and the WTA extends to 2011 and is expected to increase testing at Tier I-IV events by more than 150%.