After taking his diploma, Zoja returned to Zurich to work at a clinic for several years. He maintains a private practice in Milan. He also practiced for two years in New York City, during a period that bracketed the terrorist attacks on New York and Washington, D. C. He has taught regularly at the Zurich Jung Institute, and also on occasion at the Universities of Palermo and Insubria.
After obtaining his diploma, Zoja returned to Zurich to work at a clinic for several years. He continues to practice privately in Milan. He also worked as a physician in New York City for two years, during which time he was present when terrorist attacks occurred in both New York and Washington D.C.  He has taught regularly at the Zurich Jung Institute, and occasionally at the Universities of Palermo and Insubria.