Print quality criteria are classified and listed from the point of view of paper printability. The theoretical background of such important print quality characteristics as print density and gloss, evenness, contrast and sharpness are presented. The effects of the components of ink transfer-coverage, immobilisation and splitting-on the resulting ink film structure are discussed. The connection between roughness distribution of paper and coverage in ink transfer are examined and an improvement is proposed for the previous coverage theory of Hsu. The use of laboratory test printing and full-scale pressruns are recommended for printability evaluation of paper and the methods used in determining various print quality numbers are reviewed.