Insight is regarded as one of the most important factors in counseling. There were several studies on the relationship between insight and outcome. However, researchers focused more on how the quantity of insight impacted on the outcome, and neglected the quality of insight. Actually, the quality of insight is more important than the quantity in successful counseling. Few published papers has addressed the quality of insight. This study attempts to explore how to evaluate the quality of insight from the perspectives of both clients and counselors. Insight is defined as a new understanding of oneself and others (mainly oneself) in this study. Thirteen clients and fifteen counselors consent to participate in the study. The participants are interviewed face-to-face regarding to their experience of insight in counseling. When the clients have received three or more sessions, they are asked to review a recent session. After that, they are asked to describe the insight in this session and rate the quality of insight. The counselors are asked to list two or three insights obtained by the clients in recent counseling sessions. Then they are asked to rate the quality of insight separately. The reasons why they rate are interviewed. All the interviews are recorded and transcribed. The interview materials of clients are analyzed by a research team (4 counseling-major postgraduates) using Consensual Qualitative Research (CQR), while the data of counselors are analyzed by another research team (3 counseling-major postgraduates). For clients, there are two themes emerging from the interview data. The first theme centers on the impact of insight ( T ). Two subcategories are included in this theme. One is helpfulness ( T ), and the other is emotional arousal ( V ). The second theme centers on the properties of insight ( T ). There are four subcategories belonged to this theme, which includes depth ( V ), discrepancy ( V ), centrality ( V ), and controllability ( V ) separately. For counselors, five themes are extracted from the interview data. The first theme (including subcategories) is highly similar to the results of the clients, which centers on the impact of insight. The second theme is also very similar to the results of the clients, which centers on the properties of insight. There are five subcategories under the second theme. They are depth ( V ), discrepancy ( V ), centrality ( V ), the connection of experience ( V ), and accuracy ( V ). Among the subcategories, depth, discrepancy and centrality are similar with clients’ views. The third theme centers on the type of insight ( V ). There are two different types of insights. Overall, emotional insight is better than intellectual insight for counselors. The fourth theme centers on the way of gaining insight. Insights obtained by clients themselves are better than that offered by counselors. The fifth theme centers on the extent of acceptance ( V ). As a whole, there are many similarities between counselor’ and clients’ views about quality of insight. Both of them emphasize the impact of insight including helpfulness and emotional arousal. In addition, both of them pay attention to the properties including depth, discrepancy, and centrality. The impact of insight and some important properties of insight (such as depth, discrepancy, centrality ) are important to the quality of insight, which may be used tentatively to assess the quality of insight. These results have important implications for clinical practice and research.