The paper focus on today´s, cost-effective electronics, microcomputers, and digital signal processors have brought new advanced technology to appliances and consumer products. Systems with precision sensors and actuators have increased performance by order of magnitude over what was once possible. The paper discusses what set these new, high-performance, cost-effective systems and devices apart from those of the past? Is it more than just technological advancement? There are many designs where electronics and control are combined with mechanical components, but with very little synergy and poor integration they just become a marginally useful, error-prone, expensive conglomeration. Synergism and integration in design set a Mechatronic System apart from a traditional, multidiciplinary system. So there is a need for new design methods and educational needs to make mechanical engineers become successful mechatronic engineers. The paper presents and discusses new mechtonic design approach and design methods anr IT-Tools used to demonstrate such approach and IT-Tool for modelling, simulation and control useful in analysis, synthesis, design and application of mechatronic systems with fluid power actuation. The focus is on system aspects and describes several projects from education and research that utilises the mentioned methods and techniques.