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We present new long-term CCD photometry for EP And acquired during the period2007 to 2012. The light curves display total eclipses at primary minima andseason-to-season light variability. Our synthesis for all available lightcurves indicates that the eclipsing pair is a W-type overcontact binary withparameters of q=2.578, i=83.3 deg, $\Delta T$=27 K, f=28 %, and l3=2~3 %. Theasymmetric light curves in 2007 were satisfactorily modeled by a cool spot oneither of the eclipsing components from a magnetic dynamo. Including our 95timing measurements, a total of 414 times of minimum light spanning about 82 yrwere used for a period study. A detailed analysis of the eclipse timing diagramrevealed that the orbital period of EP And has varied as a combination of anupward-opening parabola and two periodic variations, with cycle lengths ofP3=44.6 yr and P4=1.834 yr and semi-amplitudes of K3=0.0100 d and K4=0.0039 d,respectively. The observed period increase at a fractional rate of+1.39x10^{-10} is in excellent agreement with that calculated from the W-D codeand can be plausibly explained by some combination of mass transfer from theprimary to the secondary star and angular momentum loss due to magneticbraking. The most reasonable explanation for both cycles is a pair oflight-travel-time effects driven by the possible existence of a third andfourth component with projected masses of M3=0.25 Msun and M4=0.90 Msun. Themore massive companion could be revealed using high-resolution spectroscopicdata extending over the course of a few years and could also be a binaryitself. It is possible that the circumbinary objects may have played animportant role in the formation and evolution of the eclipsing pair, whichwould cause it to have a short initial orbital period and thus evolve into anovercontact configuration by angular momentum loss.

The Eclipsing System EP Andromedae and its Circumbinary Companions