Top: long-term spin frequency history of SAX J2103.5+4545 since its discovery in 1997. To visualize this plot more clearly we do not display the results from Baykal et al. (2002, 2007), our first XRT frequency determination from Table 3, and some values from Sidoli et al. (2005). Middle: long-term optical light curve of this source. Bottom: history of the outbursts during the same period. The peak intensities of the different outbursts are only intended to be illustrative of the times and types of events since they have not been corrected for the different energy bands. The long-term evolution of the H_α EW (blue triangles, stars, and filled circles) is also overplotted.