Pratt & Whitney (United Technologies group company), which also provides jet engines to both military and commercial aircrafts, is under development of new regional aircraft MRJ (Mitsubishi Regional Jet) and Bombardier CSeries. Pratt & Whitney is already providing engines for CRJ (Canadian Regional Jet) and basically still not as well known as Rolls Royce or GE for the passenger aircraft business.
Next 20 years, around 5000 regional jets are expected to be on demand (according to Mitsubishi) currently dominated by just a few smaller aircraft makers (Airbus and Boeing seem not entering into the market yet).
Smaller and cost efficient as well as economical passenger aircrafts are needed and Pratt & Whitney seems leading the market - regional jet engine supplier (of course bigger commercial airplanes as well).