In the years 1976–1999, Pia trained in Zen in Kamakura, Kanagawa/Japan with Hugo Makibi Enomiya-Lassalle and Yamada Kôun Roshi in Hawaii. She received Dharma transmission from Aitken Rōshi and in 1999 she was confirmed as Zen master by Zen Master Bernard Glassman.
In 1969 Pia joined the ecumenical community with inter-religious orientation Saint Katharina-Werk in Basel, Switzerland. On behalf of the Federal Department of Justice and Police she founded. in 1976, a therapy home near Horw for particularly difficult young persons which she led until 1982. Subsequently she was nominated general leader of the Saint Katharina-Werk. In 1986 she founded a project for meetings of the world’s religions and in 1989 she initiated in a slum on the outskirts of Manila a school for the spiritual and political awareness of young people. In 1995, back in Switzerland, she founded together with Niklaus Brantschen, Jesuit Priest and Zen Master, the Lassalle-Institute of Zen – Ethics – Leadership which they led until 2002 and at which she and Brantschen founded in 2003 the Glassman-Lassalle-Zen-line and the school of contemplation “Via Integralis”. After that they developed a peace project in Jerusalem – Open town for learning about peace in the world. This program is accredited at the UN and led them regularly to Jerusalem and to New York.