Abstract. In the paper we address the properties of fast ion driven TAEs and other Alfvén eigenmodes in NSTX and JT-60U, and in planned burning plasma devices of ITER, FIRE, and IGNITOR for the US Next Step Option consideration. The study of Alfvén instabilities is important because they could enhance the loss of auxiliary heated fast ions and alpha particles in burning plasmas. For NSTX we will present TAE results observed even for a modest NBI power and compare the experimental results with theoretical analysis. For JT-60U we will present theoretical interpretations for TAE experimental results in normal shear discharges, and the measurement of q profile in the plasma core in terms of the observed TAE frequencies. For the planned burning plasma devices we will present TAE stability analysis and summarize the parameter domain where TAEs are expected to be unstable. The stability of TAE-type modes and other Alfvén eigenmodes are performed with numerical analysis employing global kinetic-MHD stability codes, a perturbative NOVA-K code and a non-perturbative NOVA-2 code, and a high-n code, HINST code.