A short history of Dutch dune vegetation research is presented as an introduction to the present research in the Delta region. Remarkably enough the main results of dune research were presented as dissertations. The classics F. Holkema, L. Vuyck, J. Jeswiet, J. Bijhouwer and W. van Dieren are mentioned. The broadening basis is marked by the outstanding thesis of V. Westhoff, the first all-round phytosociological and ecological study of Dutch dunes. New ideas from this work are mentioned. The work of some pupils and collaborators of Westhoff is discussed. The new approach consists of concentration of the research in the Delta region, development of new ideas and establishment of field stations in the dunes. The scientific value of the Delta dunes is treated. Especially the Voorne dunes are considered as outstanding. Some future changes that threaten the area, are mentioned. The organisation of the Delta dune research is discussed, especially the work of a special Research Group, operating from the Biological Station “Weevers’ Duin” at Voorne. The current botanical problems are treated. It is stressed that they are placed in the framework of the ecological relation theory of C. G. van Leeuwen, which is a new, highly stimulating, system-theoretical approach. This relation theory is introduced and commented. Four environmental types are treated, the uniform, the variegated, the ecotone and the ecocline environment. The dune environment is discussed as a system of gradients. The main gradients are mentioned: the zonation of dry dunes, zonation of slacks, gradient from sea dunes towards estuaries, the complex salt-fresh gradient, the complex wet-dry gradient, and the complex gradient in the human and animal factors. The dune vegetation is treated as a continuum. 24 vegetational series are mentioned. A series consists of closely related communities, forming a continuum. Some problems concerning selection and sampling are discussed. The controversy between Anglo-American and Ziirich-Montpellier scholars is elucidated on some points. The Braun-Blanquet scale of combined estimation is advocated. The study of pattern and instability in vegetation research is emphasized. Some methods in structure analysis are mentioned. Recent problems in vegetation systematics are discussed. The application of methods in the Delta research is consequently mentioned. An extensive bibliography, covering important botanical work in Dutch dunes, ends the paper.