The present invention generally relates to the production of fluidic droplets. Certain aspects of the invention are generally directed to systems and methods for creating droplets by flowing a fluid from a first channel to a second channel through a plurality of side channels. The fluid exiting the side channels into the second channel may form a plurality of droplets, and in some embodiments, at very high droplet production rates. In addition, in some aspects, double or higher-order multiple emulsions may also be formed. In some embodiments, this may be achieved by forming multiple emulsions through a direct, synchronized production method and/or through the formation of a single emulsion that is collected and re-injected into a second microfluidic device to form double emulsions.