Roser has made a major contribution working with marionettes.
[4][5] Another of his characters, Grandmother, is outwardly charming but savagely humorous in her observations about all aspects of society and the absurdities of life.
[4] A large number of his tours were organised with assistance from the German Cultural Institute.
In 1977, Roser was invited to spend a semester as guest artist at the University of Connecticut, United States of America, by the Department of Puppetry.
In 1983 he established the Figurentheaterschule Stuttgart, a school for puppetry at the Conservatory for Music and the Dramatic Arts, where he was professor and head of the department.