Periodic dielectric structures typically require a planar waveguide to produce photonic band-edge modes for feedback in 1D distributed feedback lasers and 2D photonic crystal lasers. Photonic band-edge lasers are widely used in optics and biological applications, but limitations include low modulation speeds and diffraction-limited mode confinement. In contrast, plasmonic nanolasers can support ultrafast dynamics and ultrasmall mode volumes, but the most common designs based on an inorganic semiconducting wire and a planar metal film suffer from large radiative losses and lack far-field emission directionality. In this talk, we will discuss lasing action from band-edge lattice plasmons in arrays of plasmonic nanocavities in a homogeneous dielectric environment.1 Optically pumped, 2D arrays of plasmonic (Au, Ag) nanoparticles surrounded by an organic gain medium can show directional beam emission (divergence angle < 1.5° and linewidth < 1.3 nm) characteristic of lasing action in the far-field. Lasing in such hybrid systems can be achieved from stimulated energy transfer from the gain to the band-edge lattice plasmons in the deep subwavelength vicinity of individual nanoparticles.