In the phase-field method for fracture, cracks are represented in a diffusive manner rather than as sharp discontinuities. This continuous description enables a numerically robust treatment of intricate crack patterns, including merging and branching cracks, which poses considerable challenges for discrete approaches such as XFEM/GFEM, particularly in 3D. However, using standard discretizations, the accuracy of the phase-field formulation strongly depends on a sufficiently fine mesh near the crack, as both the phase-field variable and the displacement field as well as their gradients must be adequately captured, which increases computational effort. The extended phase-field method (XPFM) [1] is based on the concept of the XFEM/GFEM, extending and adapting the ansatz functions to incorporate information about the expected solution. This information is derived from the analytical solution of a one-dimensional problem with a given crack position and extended to 2D. For the phase-field approximation, an exponential-type transformation is obtained, into which the standard Lagrangean shape functions are inserted, allowing the phase-field profile perpendicular to the crack to be reproduced very accurately. The standard displacement ansatz is extended by an additional term which contains modified shape-functions which are calculated for each enriched element on a sub-problem (detailed in part 2 of this contribution). This enrichment enables the capturing of the high and stiffness-degradation-dependent displacement gradients across the crack. In this contribution, the XPFM framework is presented, including the transformed phase-field ansatz and the enriched displacement field ansatz as well as the general enrichment scheme and further algorithmic aspects. Examples are shown to display the efficacy of the method. REFERENCES [1] S. Loehnert, C. Kr¨uger, V. Klempt and L. Munk, An enriched phase-field method for the efficient simulation of fracture processes, Comput. Mech., Vol. 71, pp. 1015–1039, 2023.