Apparatus for handling partially formed or fully formed cartons each having a mid-portion of predetermined cross-section includes rollers (68) arranged to press on respective mid-portions of respective upright edges of one of a plurality of pairs of adjacent upright edges of each carton, so as to make the mid-portion of the cartons of rounder cross-section. The rollers (68) are provided with respective projections (70) arranged to bear on a carton between the rollers (68). Respective biassing devices serve to bias the rollers (68) into respective home angular positions. Upper and lower endless conveying belts (52 and 54) advance the cartons relative to the rollers (68). The rollers (68) are offset along the path of advance by said advancing arrangement.
