Abstract: Methods, systems, and articles of manufacture are provided for manipulating partitions while imaging them to another disk on the same or another computer. By integrating partition manipulations with imaging, the invention reduces data movement. Rather than resizing a source partition in place and then imaging the resized source partition, for instance, one embodiment of the invention leaves the source partition intact and performs resizing on-the-fly by manipulating a memory-resident copy of the source partition's file system structures and then copying the modified structures and corresponding portions of the source user data to the target location. In addition to partition resizing, on-the-fly manipulations possible with the invention include cluster resizing, defragmentation, file relocation, and others. Novel image file formats suitable for on-the-fly manipulations are also described.