What are the relative merits and drawbacks of parliamentary and presidential systems? Why have most East European countries adopted parliamentary systems?

There has been much argument amongst political academics concerning the virtues and failures of both parliamentary and presidential systems. While all systems of governance vary from country to country, parliamentary systems can broadly be defined as where the executive, in the form of a prime minister and his cabinet are drawn from the elected legislature (parliament). In presidential systems however the executive (president) is elected separately from the legislature and members of the executive cabinet …

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