The blending of thermosetting polymers (TS) with high performance thermoplastics (HTP) is an effective pathway to design new advanced materials that meet the requirements of demanding sectors such as aerospace, electronics, or high performance structural applications requiring durability under thermal and mechanical stress. Although offering high mechanical properties, thermal stability and chemical resistance, TS resins often suffer from brittleness, that can be improved with the addition of a tougher HTP material, such as polyetherimides, polysulfones or polyetherketones. This study will firstly provide an overview of recent developments in the formulation, processing, and characterization of TS/HTPs blends. It highlights the fundamental challenges induced by the chemical and physical differences between TS and HTPs systems, especially their low miscibility and limited interfacial adhesion, which often lead to unstable morphologies and poor mechanical synergy. Various processing methods such as melt blending, solution casting, in situ polymerization or co-curing are analyzed, with particular focus on their impact on phase morphology and distribution. Compatibilization strategies, including the use of reactive copolymers, functional additives, or chemical modifications, have proven effective in improving interfacial interactions and promoting the formation of stable microstructures. Thereafter, special attention is given to systems displaying co-continuous morphologies or forming interpenetrating polymer networks (IPNs), as they often offer an optimal balance between stiffness, toughness, and long-term thermal resistance. Despite promising pioneering reports, the relationships between processing conditions, interfacial phenomena, and final material properties remain complex and not yet fully understood. Therefore advances in interfacial engineering, molecular-level modeling, and specific characterization techniques of these hybrid systems are necessary to unlock their full potential and enable their broader implementation in high-performance applications.