Data on a sample of 98 Lebanese secondary schools--representative of the country's urban, rural, public, private, Moslem, and Christian schools--were used to test F. E. Fiedler's hypothesis that school effectiveness is related to the match between the principal's style and his or her school's "situational favorableness." School effectiveness was measured by teacher job satisfaction and by student scores on three sets of national tests. Principal style was defined as the principal's orientation toward relationships or toward task accomplishment. Situational favorableness comprised the principal's authority or power position, school leader-member relations, and the structure of school tasks. Data on these factors were gathered from surveys of 98 principals and 728 teachers and from test scores on 2,999 students. Statistical analysis using regressions, correlations, and t-tests failed to support Fiedler's hypothesis but did indicate, among other things, that good leader-member relations and strong principal power position correlated highly with teacher satisfaction and high scores on one of the national tests. (RW)