Theprefacetoatextbookfrequentlycontainstheauthor'sjustificationforofferingthepublic"anotherbook"onthegivensubject.Forourchosentopic,thearithmeticofellipticcurves,thereislittleneedforsuchanapologia.Consideringthevastamountofresearchcurrentlybeingdoneinthisarea,thepaucityofintroductorytextsissomewhatsurprising.PartsofthetheoryarecontainedinvariousbooksofLang(especially[La3]and[La5]);andtherearebooksofKoblitz([Ko])andRobert([Rob],nowoutofprint)whichconcentratemostlyontheanalyticandmodulartheory.Ina