Entry inwards requirement controls unloading of imported goods, with limited exceptions for baggage, mail, animals, perishables, and hazardous goods. Imported goods cannot be unloaded from a vessel until the proper officer grants entry inwards. The order may be issued only after the arrival manifest or import manifest has been delivered, or if sufficient cause for non-delivery is shown. The restriction does not apply to baggage accompanying passengers or crew, mail bags, animals, perishable goods, or hazardous goods.