The AceFEM environment comes with a small build-in library including standard solid, structural, thermal and contact elements. Additional elements are accessed and automatically downloadable through the AceShare system. The AceShare system is a file sharing system built in AceFEM that makes AceGen symbolic descriptions and generated finite element user subroutines available for other users to download over the Internet. The AceShere system enables: browsing the on-line FEM libraries; downloading the finite elements from the on-line libraries; formation of the user defined library that can be posted on the internet to be used by other users of the AceFEM system. The AceShare system offers for each finite element included in the on-line library: the element home page with basic descriptions, links, authors data, etc.. , the AceGen template (Mathematica input) for the symbolic description of the element, the element source codes for all supported finite element  environments (FEAP, AceFEM-MDriver, Abaqus, ...), the element Dynamic Link File (dll) used by AceFEM, an additional documentation and benchmark tests. The files are stored on and served by personal computers of the users.

The already available AceShare on-line libraries include AceGen templates for the symbolic description of direct and sensitivity analysis of the most finite element formulations that appear in the description of problems by finite element method (steady state, transient, coupled and coupled transient problems). This large collection of prepared Mathematica inputs for a broad range of finite elements can be easily adjusted for users specific problem. The user can use the Mathematica input file as a template for the introduction of  modifications to the available formulation (e.g. modified material model) or combine several Mathematica input files into one that would create a coupled finite element (e.g. the AceGen input files for solid and thermal conduction elements can be combined into new AceGen input file that would create a finite element for thermomechanical analysis).