The CRISP package Version 1.3 The GAP package CRISP provides algorithms for computing subgroups of finite solvable groups related to a group class C. In particular, it allows to compute C-radicals and C-injectors for Fitting classes (and Fitting sets) C, C-residuals for formations C, and C-projectors for Schunck classes C. In order to carry out these computations, the group class C must be represented by an algorithm which can decide membership in the group class. Moreover, CRISP contains algorithms for the computation of normal subgroups invariant under a prescribed set of automorphisms and belonging to a given group class. This includes an improved method to compute the set of all normal subgroups of a finite solvable group, its characteristic subgroups, and the socle and p-socles for given primes p. This version of CRISP requires at least GAP 4.4.12. In order to install CRISP, you have to get the current package archive file `crisp-1r3n5.tar.gz', or any other package format suitable for your system. You can download the current package archive from the packages section of www.gap-system.org. To install CRISP, move the downloaded package archive file into the `pkg' directory in which you plan to install CRISP. Usually, this will be the directory `pkg' in the GAP directory. If you already have a previous version of CRISP, that is, there is a directory `crisp' in the `pkg' directory, delete (or rename) this directory first. Then decompress the package archive. You should now have a directory `crisp' in the `pkg' directory. That's all. By default, CRISP is automatically loaded when you start GAP, and should be listed among the loaded packages. To load the CRISP package manually, type LoadPackage ("crisp"); at the GAP prompt. If everything is ok, this should return `true'. Please do not hesitate to report any bugs or other problems/suggestions to the author: Burkhard Hšofling WWW: http://www.icm.tu-bs.de/~bhoeflin e-mail: b.hoefling@tu-bs.de