Starting from the Swedish curriculum’s goals of a school for all children this study’smain purpose is to contribute to the understanding of how mental number-lines arebeing described and related to by people with visualized number-forms. The study aimsto answer the two questions:- How are the mental number-lines described by people with visualized numberformsand in what way do these descriptions differ from a conventional numberline?- What relations can be found between the visualized number-line and the choiceof counting-strategies on number-tasks?The study used a qualitative method in which three participants with visual mentalnumber-lines described their preferred counting-strategies and relation to their mentalnumber-lines in three semi-structured interviews. The data was then analyzed byconnecting counting-strategies to the described mental number-lines and by comparingthe described mental number-lines to conventional, linear, number-lines. Two of theparticipants in the study displayed a distinct connection between counting-strategies andnumber-line-visualization. This was shown by the way they adapted their countingstrategiesto fit their personal visualization of the mental number-line. The resulthighlights the importance of understanding how students visualize their number-lines.For further studies this study suggests further investigations regarding how mentalnumber-line-visualizations hinders students from achieving important steps in theirunderstanding of mathematics.