Consistency with quantum gravity and black hole physics puts significant constraints on low-energy effective field theories. In fact, most EFT’s do not satisfy these criteria, and are said to be in the “Swampland”. After a brief introduction, I will focus on two recently discovered Swampland constraints: A pandemic of Chern-Simons terms in effective field theories coming from string theory, and a rigorous bound on the gauge coupling of any U(1) theory coupled to gravity in AdS space. This is equivalent to a bound on the large N behaviour of the current 2-point function of any holographic CFT. Finally, I will also comment on attempts at a proof of the Weak Gravity Conjecture using holography, including a possible relation with the Complexity=Action proposal.