When Gabriel Almost first introduced the structural-functional approach to comparative politics in the 1970s, it represented a vast improvement over the then-prevailing mechanistic theories of David Eaton and others derived largely from international relations. Almond's brilliant innovation was to outline an approach to understanding political systems that took into account not only its structural components — its institutions — but also their functions within the system as a whole. Prior to structural functionalism, scholars had no way of systematically comparing different political systems beyond a rudimentary, and oftentimes inconclusive, analysis of their institutions.

At its most basic level, the model of structural functionalism posits that a political system is made up of institutions (structures), such as interest groups, political parties, the executive, legislative and judicial branches of government, and a bureaucratic machinery. This information is not sufficient, however, to make a meaningful comparison between two political systems. Two countries may share many of the same political institutions, but what distinguishes the two systems are the ways in which these institutions function.

For Almond, a fuller understanding emerges only when one begins to examine how institutions act within the political process. As he described it, interest groups serve to articulate political issues; parties then aggregate and express them in a coherent and meaningful way; government in turn enacts public policies to address them; and bureaucracies finally regulate and adjudicate them.

While this model neatly accounts for what happens within a political system, systems are never entirely self-contained. They exist in a dynamic relationship to other political systems and must continuously adapt to changing conditions in the larger socio-political context. For this reason, all political systems require efficient feedback mechanisms.

Gabriel Almond and his colleague Bingham Powell, in modifying and expanding the theory of structural functionalism, have added an important set of system functions to their model in recent years. This change acknowledges the crucial role played by political culture in determining the unique characteristics of a political system. These system functions include political socialization, recruitment, and communication. Without understanding these elements of a society, it is difficult, if not impossible, to make an adequate assessment and comparison between two political systems.

By political socialization, Almond and Powell mean the process by which a culture passes down civic values, beliefs, and habits of mind to succeeding generations. It refers to the largely unconscious process by which families, schools, communities, political parties and other agents of socialization inculcate the culture's dominant political values. Recruitment refers to the ways by which citizens become active participants in the political system. And communication represents the way a political system disseminates information essential to its proper functioning. For example, the news media plays a vital role not only in distributing public information to citizens upon which they then make important political decisions, but also — as Shanto Iyengar and other scholars have shown — in shaping political attitudes and values concerning the political process.

The structural functional approach contains within it several inherent biases or normative implications. First, it is by its very nature conservative: it recognizes that a political system's first objective is to ensure its own survival. For this reason, it is not especially responsive to innovations and movements aimed at political change — that is, beyond those that strengthen its adaptiveness and resilience. It also has a democratic and participatory bias insofar as it views citizen input and involvement in the political process as the surest route to political stability and responsiveness.

But what Almond and Powell have yet to give us, in my view, is a model that gives adequate attention to the role of civil society in shaping political culture. Civil society refers to the wealth of institutions, associations, and citizen groups that operate outside and independent of either government or business. As we have seen in Eastern Europe and elsewhere, civil society can go a long way toward shaping the political fate of a nation. As Robert Putnam and by now a host of other sociologists have convincingly demonstrated, it is also a chief determinant of a political system's overall stability and effectiveness. Almond and Powell's model alone does very little in helping us understand the role of civil society in shaping political culture and still less how it differs between different political systems.