School improvement initiatives are needed to better meet the needs of underprivileged students, to reduce underachievement and to break a continuing cycle of disadvantage. This article describes part of a school improvement initiative in New Zealand that provided additional funding for school nurse and social worker services in nine secondary schools with the most disadvantaged students in New Zealand. It describes the nature and delivery of services provided by the social workers in these schools. In addition, the article reports changes over time in staff and student views about school climate including a comparison with non-participating schools of similar socioeconomic status. The findings indicated that school climate is a useful intermediate measure of the effectiveness of school improvement initiatives. There were significant improvements in staff views about school climate over time, with staff views about school climate becoming more favourable on scales measuring Improvements in the Last 12 Months and Support for Ethnic Diversity compared to eight non-participating schools. Student views were more favourable on scales measuring Satisfaction with School, Support for Achievement and Support for Ethnic Diversity, compared to the non-participating schools.