Church attendance in the U.S. is declining. The growth of large mega church congregations gives the appearance that church attendance is increasing, when in actuality, attendance at 80% of churches in the U.S. is not increasing. Church leaders are not in agreement regarding the significance of pastoral leadership on the problem of declining church population; many seminaries do not teach leadership. The purpose of this quantitative correlational study was to determine if a relationship existed between the leadership behaviors of senior pastors and the rate of church growth. The entire populations of churches within the Church of the United Brethren in Christ and the Missionary Church denominations located within the United States were surveyed; excluding church congregations that had a change in senior pastoral leadership during the survey period. There were 376 pastors eligible to be studied in the two denominations. Data were collected from 76 pastors using the Leadership Practices Inventory-Observer (LPI). Kendall's Correlation Coefficient was conducted to determine the relationship between the construct of leadership measured by the LPI and church population growth. None of the five leadership behaviors were found to be significantly related to church population growth. The highest regression coefficient scored 0.138 (p = .080). Regression analyses were conducted by the researcher to attempt to predict which of the five leadership behaviors would influence church growth. None of the behaviors significantly predicted church population growth where the highest R² scored 0.041 (SD = .004, p = 0.081). The regression analyses were moderated for church size and the results found by the researcher did not show any significant relationship between leadership behaviors of senior pastors and church growth where the highest R² scored 0.086 (SD = .004, p = 0.075). Future researchers might consider studying denominations with more church congregations or denominations with larger congregations. Another suggestion for future research is a comparison of leadership behaviors between the pastors of growing church congregations and the leadership behaviors of pastors of declining church congregations.