Lowe Roche is without a CEO as Monica Ruffo has left the Toronto-based agency.

Marie-Lise Campeau, managing director at Lowe Roche, confirmed in an email Ruffo has left the shop. Further questions were directed to Lowe and Partners, the agency’s parent company.

“After three years of service, Monica Ruffo will be leaving Lowe Roche,” Michael Wall, Lowe and Partners’ global CEO, said in an emailed statement. “Monica is a great talent who helped serve the needs of our clients. We wish her all the best as she embarks on her next chapter. A succession plan will be announced soon. Until then, the experienced Lowe Roche management team is overseeing the agency.”

Ruffo took on the CEO role in 2011 after agency co-founder Geoffrey Roche decided to leave the advertising industry. She had previously been CEO of Amuse, a Montreal-based boutique agency she founded, which was purchased by Lowe and Partners upon her taking the new role. She continued to run both agencies during her tenure.

The status of Amuse following Ruffo’s departure was not addressed in Wall’s statement. When contacted, Ruffo said she would not be making a comment.

Before leaving to start Amuse in 2008, Ruffo was EVP and global chief strategy officer at Cossette, a role she had for eight months, following five years as president at what was then Cossette Nucleus, the agency’s strategic planning arm.