A parcel transfer system transfers a parcel or a similar article directly between a conveyor and a self-driving vehicle (“SDV”) while the conveyor and SDV are moving. The conveyor, SDV, or both may be configured to initially transport a parcel in a first direction of travel and then subsequently offload the parcel in a second direction of travel. The SDV is configured to travel alongside of the conveyor in the first direction of travel and either receive the parcel as it is offloaded from the conveyor or offload the parcel onto the conveyor in the second direction of travel. The parcel transfer system further includes a vision and control subsystem, which regulates movement of the SDV and offloading of the parcel from the conveyor or SDV.