Abstract: In this paper, single pile lateral load capacity has been analyzed, based upon test results on four cast-in-situ concrete piles installed with "jetting and suction" drill, different in length, diameter and percentage of reinforcement.Criteria for determining single pile critical cracking load have been investigated. For three of the four piles were instrumented, and bending moments on different sections have been figured from measured REBAR stresses on these sections; such bending moments figured from REBAR stresses have been compared with theoretical values of bending moments computed from four methods currently accepted at home and abroad. Values of soil moduli have been back-figured from measured pile-head lateral movements at ground level, and a tentative rule for variation of soil moduli as a function of pile-head displacement has been suggested. Computed pile-head angular displacements have been compared with values measured in the field. Finally, influences of variation in pile length, diameter and percentage of reinforcement on the lateral load capacity for single-piles are preliminarily studied.