After 1950, he was active in Catholic relief work worldwide, through church appeals, public speaking, and his newsletter, The Mirror, which he began publishing in 1953.
After the plight of the expellees in the newly founded Federal Republic of Germany was largely alleviated, his concern became the persecuted church in the now communist-dominated Eastern Europe.
At the 3rd International Congress Treffpunkt Weltkirche, held from 11 to 13 April 2008, in Augsburg, the Father Werenfried Prize was awarded for the first time to the Friends of the St. Clemens Church in Berlin.
At the 5th international congress of Treffpunkt Weltkirche, held from 12 to 15 March 2015, in Würzburg, the Father Werenfried Prize was awarded to Gabriele Kuby.
In 2021 Die Zeit published an article which made known the existence of a letter from 2010 indicating that Van Straaten was accused of committing sexual assault in 1973 against a 20-year-old woman working for the charity.
[2][3] In a statement consisting of questions and answers, Aid to the Church in Need responded to the disclosure and noted that "ACN deeply regrets the serious allegations and condemns any kind of behavior of which Father van Straaten has been accused in the article.