We investigated in two different sites (which differed by the breeds present and by the amount of human contact) the influence of the establishment of positive human-mare relationships on foals’ behaviour toward humans. Twenty-one mares were softly brushed and fed by hand during a short period (total of 1.25 hours) during the first 5 days of their foals’ lives (experimental group), whereas 20 other mares were not handled experimentally and their foals received no contact with the experimenter (control group). The reactions of both experimental and control foals were recorded under various conditions (presence of a motionless experimenter, approach test, saddle-pad tolerance test) when they were 30-35 days old. Approach-stroking tests were also performed successively by the familiar experimenter and by an unfamiliar person when they were one year old. Several observations strongly suggest that mares can influence their foals’ behaviour toward humans: 1) During the handling procedure, experimental foals of protective mares were further from the handler than foals of calm mares (Spearman: Stud 1, rs = -0.79, p < 0.01; Stud 2, rs = -0.83, p < 0.01). 2) Experimental foals remained, at all ages, closer to the experimenter (Mann-Whitney: Stud 1 & 2, p < 0.05) and initiated more physical contacts with the experimenter (M-W: Stud 1 & 2, p < 0.05) than control foals. 3) Avoidance and flight responses of experimental foals were considerably reduced during approaches by the experimenter (M-W: Stud 1 & 2, p < 0.01) and they accepted saddle-pads on their back more easily (M-W: Stud 1 & 2, p < 0.01) and more quickly (M-W: Stud 1 & 2, p < 0.01) than control foals. Finally, the consequences of handling mares had effects that lasted at least until foals were one year old (M-W: Stud 2, p < 0.05) and were generalized from experimenter to unfamiliar humans. Similar results were interestingly found in both studs. This is the first report of an attempt to use observation of mother by foals to facilitate human-foal relationships.