Fr. Adrien Schoonen spent six years (1952-1958) at the SMA Generalate in Rome as a member of the General Council and at the same time as the archivist. As he classified thousands of documents and letters, he found enough material to write about a topic that was crucial during and following the General Assembly 1952 – history of our Constitution. Why was he interested in the Constitution? Because, it was the tool, Fr. Planque, the first Superior General of the Society, depended on to save the identity of the Society. Some members asked to be transferred to Europe and Fr. Planque found it not only contradictory but also suicidal to the SMA. Fr. Planque looked for an oath which was later called as the ‘Solemn oath’ through which people committed themselves for life. To make it obligatory the oath was placed inside the Constitution of the SMA which is binding on all members. The SMA Constitution saw many redactions in history, at times decided in the General Assembly and at times demanded by Rome after the publication of a Bull or the adoption of the new Canon Law. Fr. Schoonen describes the reactions of different people to various changes.