Yahoo and Zillow.com have partnered to create a real estate advertising network, bringing together the second and third most trafficked property websites.

The move expands on existing partnership between Yahoo and Zillow that began in 2006, when Yahoo integrated Zillow’s home valuations on its own real estate site. The financial terms of the deal were not disclosed.

"This new partnership between Zillow and Yahoo! Real Estate creates the opportunity for agents and brokers to reach one of the largest audiences of homebuyers online when they list a home or purchase an ad," said Spencer Rascoff, Zillow COO.

"Today, Zillow offers a range of services for every stage of homeownership and we’re excited to build upon our long-standing relationship with Yahoo! Real Estate and extend our leadership in the online real estate space."

The partnership is set to go into effect later this year, but Zillow and Yahoo Real Estate are already working on sales efforts for the advertising network. Under the agreement Zillow will power all for sale listings on Yahoo Real Estate.

The deal is part of Yahoo’s strategy to focus on its core businesses such as email, news, sports, entertainment and finance.

In May, Yahoo partnered with Match.com, owned by Internet company IAC/InterActive Corp, which replaces Yahoo Personals.