This statement is False.
A rhombus is defined as a quadrilateral with all sides congruent; however, it does not have all angles congruent. In fact, in a rhombus, the opposite angles are equal, but adjacent angles are not necessarily the same. This characteristic differentiates a rhombus from a square, which is a special type of rhombus where all angles are indeed congruent (90 degrees).
To summarize, while all sides of a rhombus are equal in length, the angles can vary, making the statement incorrect.