In earlier versions of DCMTK, changes between releases had been documented in a
CHANGES.XXX file inside DCMTK's main directory.

Now, the CHANGES.XXX file has been moved to the dcmtk/doc folder with the latest
one being updated every time that a new DCMTK version is released.  Thus it
always contains all DCMTK changes between the last DCMTK release and the most
recent one.

For very recent changes, i. e. those changes to DCMTK that have been applied
after the most recent release, see the DCMTK git repository log at
http://git.dcmtk.org/ .