As scholars have observed, government agencies have ambiguous goals. Very few large sample empirical studies, however, have tested such assertions and analysed variations among organizations in the characteristics of their goals. Researchers have developed concepts of organizational goal ambiguity, including 'evaluative goal ambiguity', and 'priority goal ambiguity', and found that these goal ambiguity variables related meaningfully to financial publicness (the degree of government funding versus prices or user charges), regulatory responsibility, and other variables. This study analyses the influence of the external political environment (external political authorities and processes) on goal ambiguity in government agencies; many researchers have analysed external influences on government bureaucracies, but very few have examined the effects on the characteristics of the organizations, such as their goals. This analysis of 115 US federal agencies indicates that higher 'political salience' to Congress, the president, and the media, relates to higher levels of goal ambiguity. A newly developed analytical framework for the analysis includes components for external environmental influences, organizational characteristics, and managerial influences, with new variables that represent components of the framework. Higher levels of political salience relate to higher levels of both types of goal ambiguity; components of the framework, however, relate differently to evaluative goal ambiguity than to priority goal ambiguity. The results contribute evidence of the viability of the goal ambiguity variables and the political environment variables. The results also show the value of bringing together concepts from organization theory and political science to study the effects of political environments on characteristics of government agencies.