Schematic representation of some new algorithms introduced in ATSAS 2.4. (a) Clustering of multiple models by DAMCLUST. The program suggests the optimal way of splitting multiple models into groups based on the distance criteria (either NSD or r.m.s.d.). In the presented example, seven models are split into three groups (indicated by the dashed line), whereby there are three models in the first group while the second and the third groups contain two models each. (b) Modelling algorithms for transient complexes (SASREFMX) and unstable oligomers (GASBORMX/SASREFMX) provide means of three-dimensional structure analysis of equilibrium mixtures, if no monodisperse samples can be obtained. (c) Rigid-body modelling of complexes with addition of missing loops by CORAL, which combines the capabilities of SASREF and BUNCH. The modelling of complicated cases with incomplete structures of the subunits is possible, whereby the RANLOGS library is used for selection of templates for missing linkers. (d) A new implementation of RANCH from the EOM package enables generation of random pools containing multimeric structures having fixed symmetric cores with or without imposed symmetry for the rest of the molecule.