Currently, the focus of Family Offices seems to have shifted away from the close interconnection of the two areas of asset management and income tax asset structuring and design. There is a lack of an academic, sound, general attempt to make tax planning and tax structuring expertise accessible in a theory-driven guide. This research gap represents the primary point of reference for this dissertation. Therefore, within the framework of this monograph, the following research question was first raised and answered: (1) "Can (inter)national income tax structuring frameworks for families owning a closed Single Family Office promote the safeguarding and increase of their family wealth?" Furthermore, particularly among tax advisors of entrepreneurial families and/or families with income from employment, where previously there had been no focus on income tax asset structuring and design due to the primary emphasis on their own (entrepreneurial) activities, the question may arise whether such structures can also be gradually employed to build a significant family wealth in the first generation as well as a closed Single Family Office. In light of this, the following research question was raised and likewise answered in this dissertation: (2) "Can the examined structures be used not only at, but progressively in support of building a significant family wealth and a closed Single Family Office?".