We introduce three new commands—nop, ziop2, and ziop3—for the estimation of a three-part nested ordered probit model, two-part zero-inflated models Harris Zhao (2007, Journal Econometrics 141: 1073–1099) Brooks, Harris, Spencer (2012, Economics Letters 117: 683–686), model Sirchenko (2020, Studies in Nonlinear Dynamics 24: 1) for ordinal outcomes, with both exogenous endogenous switching. The a...