A panel system comprising: - at least one sheet-like movable panel which is substantially vertical, - a lower profile which is substantially horizontal, supports the weight of the movable panel, and acts as a guide track for the movable panel; - an upper profile which is substantially parallel with the lower profile, supports the movable panel from above, and acts as a guide track for the movable panel; - a sheet-like immovable panel which is substantially vertical and whose weight is carried by the lower profile and which is supported by the upper profile and which has a closed position and is configured to pivot to an open position in which one vertical edge of the immovable panel is pivoted in a lateral direction with respect to the lower profile; and - an opening guide track which is placed in parallel with the lower profile, supports the weight of the movable panel, and acts as a guide track for the movable panel, and on top of which the movable panel can move from the lower profile and simultaneously pivot to an open position, in which both the lower profile and the opening guide track support the weight of the movable panel; - wherein, for moving the movable panel into the open position from a closed position, in which the movable panel is parallel with the lower and upper profiles, the leading vertical edge of the movable panel is configured to follow the lower profile, and further the opposite trailing vertical edge of the movable panel is configured to move from the lower profile to the opening guide track and to follow the opening guide track when the movable panel is moving into the open position; characterized in that: - in the open position, the movable panel is placed in the space between the lower profile and the immovable panel in the open position; and - the opening angle of the movable panel in the open position, with respect to the lower profile, is not greater than 45°. - at least one sheet-like movable panel which is substantially vertical, - a lower profile which is substantially horizontal, supports the weight of the movable panel, and acts as a guide track for the movable panel; - an upper profile which is substantially parallel with the lower profile, supports the movable panel from above, and acts as a guide track for the movable panel; - a sheet-like immovable panel which is substantially vertical and whose weight is carried by the lower profile and which is supported by the upper profile and which has a closed position and is configured to pivot to an open position in which one vertical edge of the immovable panel is pivoted in a lateral direction with respect to the lower profile; and - an opening guide track which is placed in parallel with the lower profile, supports the weight of the movable panel, and acts as a guide track for the movable panel, and on top of which the movable panel can move from the lower profile and simultaneously pivot to an open position, in which both the lower profile and the opening guide track support the weight of the movable panel; - wherein, for moving the movable panel into the open position from a closed position, in which the movable panel is parallel with the lower and upper profiles, the leading vertical edge of the movable panel is configured to follow the lower profile, and further the opposite trailing vertical edge of the movable panel is configured to move from the lower profile to the opening guide track and to follow the opening guide track when the movable panel is moving into the open position; - in the open position, the movable panel is placed in the space between the lower profile and the immovable panel in the open position; and - the opening angle of the movable panel in the open position, with respect to the lower profile, is not greater than 45°.