The latest Sasa release fixes a few bugs with MIME parsing, and adds a few new concurrency features. Here is the online documentation , or a downloadable CHM file from Sourceforge is available alongside the binaries . The binaries are also available via nuget , of course. Here's the changelog: added Sasa.Concurrency.RWLock, a truly slim concurrent read/write lock switched Sasa.Dynamics.PIC to use RWLock switched Sasa.Dynamics.PIC to rely only on arrays for performance reasons Mail message parsing now doesn't use ad-hoc means to extract a body from the attachments added Sasa.Changeable<T> which encapsulates all INotifyPropertyChanged and INotifyPropertyChanging logic with no space overhead fixed an MIME HTML parsing bug fixed regex lexing added more efficient Enums class exposing static properties for various enum properties alternate views inside multipart/related no longer incorrectly dropped added well-behaved standards conforming URI encode/decode to Sasa.Uris added ...