In recent years, teleoperation has shown great potentials in different fields such as spatial, mining, under-water, etc. When teleoperation is required to be bilateral, the time delay induced by a potentially large physical distance prevents a good performance of the controller, especially in case of contact.When bilateral teleoperation is introduced to the field of medicine, a new challenge arises: the controller needs to be used in both hard and soft environments. For example, in the context of telesurgery, the robot can enter in contact with both bone (hard) and organ (soft).In an attempt to enrich existing controller designs to better suit the medical needs, an adaptive fuzzy logic controller is designed in this text. It simulates human intelligence and adapts the controller to environments of different stiffness coefficients. It is compared to three other classical controllers used in the field of bilateral teleopeartion and demonstrates very interesting potential.ii Acknowledgements First and foremost I'd like to thank God for guiding me into and through this adventure. I have learned much during thesis time.With all my heart, I want to thank my parents for their continuous and unchanging love, care and support.To my dear church family and friends, thank you so much for your prayers, suggestions and encouragements throughout this time! Thank you also for constantly reminding me that thesis is not and should not be the centre of my life.Many thanks to my classmates as well, old and new, for the fun times we had together during my master's degree.I would also like to thank my supervisor Dr. Gueaieb for his support, guidance and help.iii