Solar magnetic eruptions are dramatic sources of solar activity, and dangerous sources of space weather hazards. Observations of the solar photosphere and overlying atmosphere have given us significant insight into how these eruptions occur. In particular, the emergence of magnetic fields from the solar interior into the corona clearly plays a dominant role in generating eruptions. I will present numerical simulations investigating the role that flux emergence plays in energizing and triggering eruptions. I will then discuss projects under way to use solar observations, primarily of photospheric magnetic fields, to determine how and when such flux emergence is creating coronal structures with eruptive potential.