This study examines the stock price effects of security offerings and investigates the nature of information inferred by investors from offering announcements. Changes in share price are unrelated to characteristics of offerings such as the net amount of new financing, relative offering size, and the quality rating of debt issues. The type of security is the only significant determinant of the price response. The opposite patterns of abnormal stock returns following the announcement of completed versus cancelled offerings suggest that managers issue common stock or convertible debt when in managers' view shares are overpriced.