Today computer science has revolutionized our world and computers have become vital component of our life.It made easy for us to analyze and diagnose the medical problems and diseases.The use of Artificial Intelligence in medicine and medical sciences are on high demand.CDSS are computer applications designed to aid clinicians in making diagnostic and therapeutic decisions in patient care.They can simplify access to data needed to make decisions, provide reminders and prompts at the time of a patient encounter, and assist in establishing a diagnosis when new patterns in patient data are recognized.The work presented in this book is the proposal for design of clinical decision support systems that aims to provide the patient with background for suitable diagnosis of some kinds of fevers.The system is designed to produce the prediction of various fevers taking only general symptoms rather than clinical measures. The proposed idea tries to make a simple human efficient decision support system so that the user can assesses him that whether he/she is suffering from any kind of sever fever or it s only their misconception.It also focuses on the basics of CDSS & its related applications.