One embodiment of the present invention includes the steps of determining the optimal RAID level to implement for a given disk drive array, and to the extent applicable, making unallocated disk space available to the user in the form of unprotected disk space. The method efficiently allocates appropriate RAID volumes for the given disk drive array, and, by making the unallocated disk space available to users, allows disk drives of unequal sizes to be effectively used in the disk drive array. Another embodiment of the present invention reconfigures an existing RAID array such that the storage space available on various disk drives in the disk drive array may be used in the most efficient manner. The alternative embodiment is especially useful if an existing RAID array is upgraded by adding a disk drive to, or modified by replacing one or more disk drives in, the existing disk drive array.