The negative changes in the international financial environment which were caused by the crisis of the sub-prime mortgage market in the United States of America have had a significant effect on the global economy in spite of the conjoint efforts of the leading world economies to counter this trend. The end of 2008 and beginning of 2009 were marked by deterioration of the macroeconomic indicators as the world economy went through the largest recession in the past 60 years. The countries which heavily depend on foreign source of funding were the most affected by the consequences of the crisis. The devastating wave of the global financial crisis led both central banks of the developed economies and those of the developing economies alike to take necessary measures as the conventional monetary policies did not react adequately or the effects were very weak. These measures are unconventional in the sense that they are a clear departure from the policy implementation framework built up by central banks over the past twenty years. This paper deals with the theoretical aspect of unconventional measures of monetary policy with special emphasis on the necessary framework for classification of unconventional measures. The goal of this paper is to show the different kinds of unconventional measures of monetary policies which used by both, developed and developing countries.