A method in a wireless local area network communication device (4, 6, 400, 600), the method comprising: assigning frames to access categories, wherein the access categories comprise a first access category defined for voice traffic, a second access category defined for video traffic, a third access category defined for best effort traffic, and a fourth access category defined for background traffic, characterised by: splitting one or both of the first and second access categories which are associated with time-sensitive information into signalling and content subcategories, and keeping the third and fourth access categories unsplit, such that signalling frames of a split access category are assigned to its signalling subcategory and content frames of a split access subcategory are assigned to its content subcategory, assigning individual relative priorities to the subcategories of the split access categories and to the unsplit access categories, such that the signalling subcategory of a split access category is assigned a higher priority than its corresponding content subcategory, where each subcategory of the split access categories and each unsplit access category has a separate transmit queue (424, 426, 428, 430) associated therewith, adding frames assigned to the subcategories of the split access categories and frames assigned to the unsplit access categories to the transmit queues (424, 426, 428, 430) associated therewith; and selecting, in a manner that takes into account the individual relative priorities of the subcategories of the split access categories and the unsplit access categories, frames from a corresponding transmit queues (424, 426, 428, 430) for transmission over a wireless medium. assigning frames to access categories, wherein the access categories comprise a first access category defined for voice traffic, a second access category defined for video traffic, a third access category defined for best effort traffic, and a fourth access category defined for background traffic, characterised by: splitting one or both of the first and second access categories which are associated with time-sensitive information into signalling and content subcategories, and keeping the third and fourth access categories unsplit, such that signalling frames of a split access category are assigned to its signalling subcategory and content frames of a split access subcategory are assigned to its content subcategory, assigning individual relative priorities to the subcategories of the split access categories and to the unsplit access categories, such that the signalling subcategory of a split access category is assigned a higher priority than its corresponding content subcategory, where each subcategory of the split access categories and each unsplit access category has a separate transmit queue (424, 426, 428, 430) associated therewith, adding frames assigned to the subcategories of the split access categories and frames assigned to the unsplit access categories to the transmit queues (424, 426, 428, 430) associated therewith; and selecting, in a manner that takes into account the individual relative priorities of the subcategories of the split access categories and the unsplit access categories, frames from a corresponding transmit queues (424, 426, 428, 430) for transmission over a wireless medium. splitting one or both of the first and second access categories which are associated with time-sensitive information into signalling and content subcategories, and keeping the third and fourth access categories unsplit, such that signalling frames of a split access category are assigned to its signalling subcategory and content frames of a split access subcategory are assigned to its content subcategory, assigning individual relative priorities to the subcategories of the split access categories and to the unsplit access categories, such that the signalling subcategory of a split access category is assigned a higher priority than its corresponding content subcategory, where each subcategory of the split access categories and each unsplit access category has a separate transmit queue (424, 426, 428, 430) associated therewith, adding frames assigned to the subcategories of the split access categories and frames assigned to the unsplit access categories to the transmit queues (424, 426, 428, 430) associated therewith; and selecting, in a manner that takes into account the individual relative priorities of the subcategories of the split access categories and the unsplit access categories, frames from a corresponding transmit queues (424, 426, 428, 430) for transmission over a wireless medium.