The design of Fibre Reinforced Polymer (FRP) reinforced concrete structures is already well introduced in the US and Middle-East, and has started to gain a market share in Europe. The reduced greenhouse gases (GHGs) emission, lower energy consumption, and excellent mechanical plus electrochemical corrosion resistance properties of this type of reinforcement are recognized as superior to steel. More recently, alternative binders have become of interest to replace the (very) polluting cement out of concrete. Commonly alkali activated materials (AAM) or geopolymers are used. Impressive reductions in GHGs seem to be possible. Despite the significant advantages, the question arises whether all those upcoming changes would influence the design philosophy used. To understand the flexural behaviour of the different materials combinations, seven bending tests on beams of 300 × 20 × 24 cm3 have been performed at KU Leuven. One reference test was made out of steel reinforcement and conventional (cement-based) Concrete (BS1), two where the steel was replaced by GFRP bars of the same diameter (BG1, BG2), two with Steel rebars and Geopolymer Concrete (GeBS1, GeBS2), and the last two with GFRP rebars and Geopolymer Concrete (GeBG1, GeBG2). It showed that, despite the remarkable differences in anisotropy and stiffness of the rebars and quality of concrete mixtures, the behaviour until failure of the test beam elements is very similar. The study discusses cracking behaviour, bending behaviour, and failure modes. Based on the outcomes of this preliminary research, it seems that the same design rules can be applied independent of the binder, and reinforcement type.