The FastCSWT package provides functionality to perform a directional continuous wavelet transform on the sphere. The transform is based on the construction of the continuous spherical wavelet transform (CSWT) developed by Antoine and Vanderghynest 1999. A fast implementation of the CSWT (based on the fast spherical convolution developed by Wandelt and Gorski 2001) is also provided. The fast algorithm in the context of the CSWT, and as implemented in this package, is described in our paper: J. D. McEwen, M. P. Hobson, D. J. Mortlock, and A. N. Lasenby. Fast directional continuous spherical wavelet transform algorithms. IEEE Trans. Sig. Proc., 55(2):520-529, 2007. The library design is based on object-oriented principles and is implemented in Fortran 90. Generally one must instantiate a class object using the corresponding init routines. The instatiated object should be freed once it is no longer required with the corresponding free routine (this deallocates all memory associated with the object).