Abstract
The solar chromosphere is the true foundation of the corona and heliosphere; where the non-thermal processes start. We observe the energy input in the photosphere (waves, flows, magnetic field) but do not know what is transmitted into the corona/solar wind because the intermediate layer, the chromosphere, has 1000 times more mass and 25-50 times more energy than the upper atmosphere. The chromosphere has long been almost ignored because it is difficult to observe and understand. In this talk I will discuss how we can improve on our understanding of this important part of the solar atmosphere through modelling. I will present some recent results from our ongoing efforts to self-consistently model the solar atmosphere from the convection zone to the corona with special emphasis on the chromospheric results.