Microsoft co-founder Bill Gates and Melinda French Gates, his wife of 27 years, said they are divorcing and will continue to work together at the massive philanthropic foundation the two built to improve global health, combat climate change and bolster US education.

“After a great deal of thought and a lot of work on our relationship, we have made the decision to end our marriage,” the two said in a statement posted on Twitter. “We have raised three incredible children and built a foundation that works all over the world to enable all people to lead healthy, productive lives.”

Bill Gates is the world’s fourth-richest person. Melinda Gates, a former Microsoft manager who married Bill in 1994, has become an outspoken advocate on global health and equality for women in her role co-running the foundation. DM