An inverse shoulder prosthesis comprising a glenoid implant and a humerus implant , the glenoid implant having a glenoid body , with an articulating surface having a convex dome shape, the articulating surface defining a first right hand coordinate system having a first x-axis , a first y-axis , a first z-axis and a first point of origin , the first z-axis being a center axis of the glenoid body , the articulating surface extending into a positive direction of the first z-axis , in positive and negative directions of the first x-axis , and in positive and negative directions of the first y-axis , or the articulating surface oriented towards a humerus and the articulating surface having a base in an anterior-posterior and a lateral-medial direction, the articulating surface having a first radius in a plane defined by the first y-axis and the first z-axis ,and a second radius in a plane defined by the first x-axis and the first z-axis , or the articulating surface having a first radius in a sagittal plane, and a second radius in a frontal plane, and the humerus implant having a humeral body and an inlay , having a concave shape, the inlay having a second coordinate system having a second x-axis , a second y-axis , a second z-axis and a second point of origin , the second z-axis being the center axis of the inlay , the inlay extending into a negative direction of the second z-axis , or the concave inlay having a center axis oriented towards a glenoid of a shoulder, and the inlay having a concave shape and a base in an anterior-posterior direction and a craniocaudally direction, the inlay having an inner radius , characterized in that the second radius is in a range of 0.8 to 0.95 times of the first radius and the first radius is smaller than the inner radius of the inlay . the glenoid implant having a glenoid body , with an articulating surface having a convex dome shape, the articulating surface defining a first right hand coordinate system having a first x-axis , a first y-axis , a first z-axis and a first point of origin , the first z-axis being a center axis of the glenoid body , the articulating surface extending into a positive direction of the first z-axis , in positive and negative directions of the first x-axis , and in positive and negative directions of the first y-axis , or the articulating surface oriented towards a humerus and the articulating surface having a base in an anterior-posterior and a lateral-medial direction, the articulating surface having a first radius in a plane defined by the first y-axis and the first z-axis ,and a second radius in a plane defined by the first x-axis and the first z-axis , or the articulating surface having a first radius in a sagittal plane, and a second radius in a frontal plane, and the humerus implant having a humeral body and an inlay , having a concave shape, the inlay having a second coordinate system having a second x-axis , a second y-axis , a second z-axis and a second point of origin , the second z-axis being the center axis of the inlay , the inlay extending into a negative direction of the second z-axis , or the concave inlay having a center axis oriented towards a glenoid of a shoulder, and the inlay having a concave shape and a base in an anterior-posterior direction and a craniocaudally direction, the inlay having an inner radius , characterized in that the second radius is in a range of 0.8 to 0.95 times of the first radius and the first radius is smaller than the inner radius of the inlay . <EOS>