Teacher-student relationships have been widely researched for decades. Each day, teachers have the opportunity to directly impact students. Through a comprehensive review of literature on teacher-student relationships and school effectiveness, the researcher identified the essential components of positive teacher-student relationships and interactions, determined if teachers' interaction styles correlate to characteristics of secure or insecure attachments, and investigated whether a relationship exists between teacher-student relationships and school effectiveness as determined by Pennsylvania School Performance Profile (SPP) data in suburban-public high schools in Allegheny County, Pennsylvania. The study revealed that positive teacher-student relationships parallel with secure attachments, are crucial to student success, and are characterized by an environment of care and empathy. Positive teacher-student relationships align with characteristics of secure attachments and are represented by interpersonal interactions consisting of empathy, care, and understanding. Although student academic success is of greater likelihood when teachers have positive, secure relationships with students, the study revealed that no statistically significant relationship exists between teachers' interaction styles and SPP data in suburban-public high schools in Allegheny County, Pennsylvania. Districts should consider meaningful professional development opportunities that foster strong relationships and provide an opportunity for teachers to engage in self-reflection about the relationships they establish with students to more effectively personalize education. As this is the first study that considers teacher-student relationships and school effectiveness in Allegheny County, PA, the findings will require further research.