U radu dajemo pregled nekih svojstava potpunog četverovrha ABCD u euklidskoj ravnini. Proučavamo kružnice s promjerima AB, AC, AD, BC, BD, CD, kao i nožišne trokute i nožišne kružnice točaka A, B, C, D s obzirom na trokute BCD, ACD, ABD, ABC redom navedene. Svi prikazani rezultati su poznati iz literature, ali ih ovdje dokazujemo koristeći istu metodu. This paper presents an overview of some properties of a complete quadrangle ABCD in the Euclidean plane. We study the circles with diameters AB, AC, AD, BC, BD, and CD, as well as the pedal triangles and the pedal circles of the points A, B, C, D with respect to the triangles BCD, ACD, ABD and ABC, respectively. The presented results are known in literature, but here we prove them using a single method.