In 2019, the year when ELI-NP laser system has reached its design parameters of 10 PW, the ELI-NP Summer School is dedicated to "Nuclear Physics with High Power Lasers". The School aims at introducing PhD students and young researchers to the novel research perspectives in the physics and applications of high-power lasers, covering the following topics: High peak power ultrafast lasers, High-power laser based particle acceleration and applications, Generation of bright coherent and incoherent gamma and x-ray pulses using short pulse lasers, Laser-driven nuclear physics, Physics of dense plasmas and warm dense matter, Astrophysics and cosmology with high-power lasers, Novel bio-medical imaging and therapeutic applications, Nuclear materials imaging, transmutation and management, Strong-field QED with high-power lasers.