that are based on massive machine-type communica- tion (e.g. smart cars, smart homes, smart factories, smart cities), the importance of QoS increases. However, to maintain the desired level of QoS, it should be regulated. This chapter covers the QoS regulatory framework and its applicability in different net- works (fixed and mobile) and in different countries (regarding the development of their ICT/telecom markets). 9.1 Scope of QoS Regulation Quality of service is being monitored in most countries worldwide [1]. From a historical point of view, QoS requirements have been applied to voice services (provided by telecom operators), but more recently regulators have been incorporating minimum QoS requirements also for data services (that is, for IAS). These imposed QoS require- ments (i.e. by NRAs) can span from high-level transparency guidelines (without stricter obligations to ISPs) on how the information on traffic management techniques is disclosed to end-users, toward requirements to be satisfied given quality indicators for data network performance (i.e. IAS performance) for fixed and mobile broadband/ ultra-broadband providers. The main scope of QoS regulation is to ensure that customers experience services of good and sustainable quality. What level of QoS do customers want or need? It depends on the price-quality tradeoff from the customer's viewpoint because higher QoS tends to cost more than lower QoS for the same service (e.g. higher bitrates in fixed ultra-broadband network cost more than lower bitrates, as bigger data cap in QoS for Fixed and Mobile Ultra-Broadband, First Edition. Toni Janevski. © 2019 John Wiley & Sons Ltd. Published 2019 by John Wiley & Sons Ltd. 9 QoS Regulatory Framework mobile networks costs more than the smaller one). The question is also, what QoS are customers willing to pay for for the service? Then, what measures (if any) will be conducive enough to customers to have their services available at the QoS level that they want and need? If there were no QoS regulation, would tel