Due to the growing offshore wind energy market and the increasing interest of the oil and gas industry, there is a steadily increasing demand for the use of jack-ups all over the world. Particularly, the number of wind turbine installation vessels has increased from 2 in 2005 to 40 currently, with a yearly growth expectation of 30% till 2020. Accident statistics from the Worldwide Offshore Accident Databank show the necessity for safer designs of jack-ups and other mobile offshore platforms. A better understanding of the soil-structure interaction and an accurate determination of the limiting loading conditions can contribute to the reduction of this failure rate. Due to the growing demand of jack-ups and the necessity for safer designs, an integral parametric model is developed to study the jack-up response comprehensively. The jack-up model combines a force resultant soil-spudcan interaction model with a structural model of the jack-up, both with 6 degrees of freedom. An illustration of the jack-up model is presented in Figure i. Environmental loads (wind-, wave- and current loads) are applied to the structural model to determine the load distribution in the jack-up structure and among the spudcans. Inputs for the jack-up model are structural properties, soil-spudcan interaction parameters, environmental conditions and preload forces. As output, the integral jack-up model provides hull and spudcan displacements for 6 degrees of freedom, internal forces and internal moments at the leg-hull connection and forces and moments applied on the soil. Furthermore, the model checks if the spudcan loads, applied to the soil, stay within the yield surface, which means that the soil response is linear elastic and the elastic soil model is valid. To assess the value of the developed integral soil-jack-up model including the chosen soil-spudcan interaction model, a comparison is made with the jack-up model combined with two other widely used soil-spudcan interaction models: a pinned soil-spudcan connection and a rotational spring connection. The comparison showed that the implemented force resultant soil-spudcan interaction model provides highly accurate results, in contradiction to the pinned and rotational spring connection. The rotational stiffness, included in the soil-spudcan interaction model, reduces the bending moment in the jack-up legs significantly. Use of the pinned soil-spudcan interaction model overestimates the bending moment in the leg. The rotational spring however, underestimates the leg bending moment. The developed jack-up model shows clearly a force distribution among the legs by means of the hull, which has a significant influence on the spudcan loads. Therefore, it can be concluded that an integral soil-jack-up model is preferred over a single leg model. A parametric sensitivity study on the soil stiffness factors showed 2 important facts. First, the rotational soil stiffness (k_r ) is the most important soil stiffness factor, since it has the greatest influence on the system response and load distribution among the legs, regardless of the applied load or reviewed spudcan load. Second, the response of the system approaches an asymptote for stiffness factors around the upper boundary values. For variation in the stiffness factor values around the lower boundary values, the system response appears to be much more sensitive. A parametric sensitivity study on structural properties of the jack-up showed the following. Increasing the spudcan radius has 3 major effects: it decreases the spudcan penetration, increases the spudcan displacements and decreases the mobilization of the rotational spudcan capacity. Adding extra legs to the jack-up results also decreases spudcan penetration and increases hull- and spudcan displacements. However, the torsional displacement and torsional moment of the hull and spudcans is reduced when extra legs are added to the jack-up. For a jack-up with one enlarged leg, the horizontal hull displacement is reduced but the torsional rotation is increased significantly. Enlargement of one leg has also a large effect on the torsional displacement of the spudcans. The enlarged leg attracts more loads than the normal legs. Due to its increased diameter, the total jack-up attracts more environmental loads.