This case study, carried out at the Institute of Professional Psycholoy, aimed to explore the efficacy of cognitive behavioural approach on a female suffering from depression. This case study aimed to see how cognitive behavioural approach can be a useful way to alleviate symptoms associated with depression and also improve client’s functioning. The client in this case study was a 40 year old female. Interview and assessment tools were used as aids for the process. Techniques from the Cognitive Behavioural Therapy Manual for Depression were used for the client’s negative thoughts and thinking biases which aimed at altering negative thoughts and in turn modify the client’s behavior Cognitive Behaviour Therapy helped the client gain insight and have control over her negative thinking process. This helped improve the client’s overall functioning and reduce depression symptoms remarkably. On the basis of the result, it can be ascertained that Cognitive Behavior Therapy is an effective approach to treat depression.