High-degree and continuity splines (or NURBS, etc.) bring to isogeometric analysis (see [1]) high accuracy per degree-of-freedom but also pose significant challenges at the com- putational level: using standard finite element routines, the computational cost grows too fast with respect to the degree, making degree raising excessively expensive. This problem is even more relevant in space-time isogeometric discretizations, that is, when adopting smooth spline discretization in space and time. We proposed in [2] a class of solvers that exploits the tensor construction of spline spaces and achieves high efficiency thanks to linear algebra tensor methods ([2]). I will then discuss the use, advantages and disadvantages, of space-time isogeometric analysis for parabolic equations and beyond. REFERENCES [1] J Austin Cottrell, Thomas JR Hughes, and Yuri Bazilevs. Isogeometric Analysis: toward integration of CAD and FEA. John Wiley & Sons, 2009. [2] Gabriele Loli, Monica Montardini, Giancarlo Sangalli, and Mattia Tani. An efficient solver for space–time isogeometric Galerkin methods for parabolic problems. Comput- ers & Mathematics with Applications, 80(11):2586–2603, 2020.