This textbook presents the most essential principles of investments. Each subject in the text is dealt with from the standpoint of an individual "ratiomal" investor who makes investments decisions under the efficient market conditions. In the textbook the detailed discussion of the investment setting is deliberately omitted in order to concentrate on the analyses of basic securities and alternative securities. On the other hand the textbook is structured to reflect these well-known steps of the investment process: identification valuation selection of assets and forming the portfolio monitoring and modifying. Moreover to the end of the textbook a list of suffested readings a glossary and an index are appended to maximize the benefits from the book.