Professors use various strategies to improve learning. To explore what professors perceived as critical aspects of engaging instruction, we conducted a qualitative case study with seven professors in the United States. Data was collected through individual face-to-face interviews. The conversations were audio-taped and transcribed verbatim. The analyses of the transcriptions were conducted using the constant comparative method. Findings from the study varied. Yet, participants agreed that an engaging instructor must focus on learning; consider various aspects of students' personal development including their cognitive, social, and emotional development; and take care of different student learning styles, for example, visual, auditory, and kinesthetic. Participants stressed the importance of student engagement. Body language, verbal and non-verbal cues, and eye contact were the main parameters used by the participants to evaluate student engagement. Participants also emphasized the importance of asking questions and assessing instructional effectiveness by evaluating the questions asked by students.