Lean over the years has become a “buzz” word. Started with lean manufacturing in the late 80s (rebranding the Toyota Production System) [1], and nowadays the term “Lean” can be found almost everywhere, just to offer some examples: lean services, lean entrepreneurship, lean software development, lean product development, lean accounting, lean startups and the list goes on and on. The underlying concept though is the same; maximize the customer value with minimum waste, i.e. “manufacturing / delivering more with less”. Although, the term “lean” is widely understood nowadays, implementing lean still poses a number of challenges. The successful lean transformation, as described the process of a company moving from an old way of thinking to lean thinking by lean experts and practitioners, relies in a big number of factors. The identification and ranking of these critical success factors have been the focus of a big number of studies. Salonitis and Tsinopoulos [2] based on an extensive review of the available literature, identified several key success factors, including: “Organisational culture and ownership”, “Developing organisational readiness”, “Management commitment and capability”, “Providing adequate resources to support change”, “External support from consultants in the first instance”, “Effective communication and engagement”, “Strategic approach to improvements”, “Teamwork and joined-up whole systems thinking”, and “Timing to set realistic timescales for change and to make effective use of commitments and enthusiasm for change”. Zargun and AlAshhab [3], in a similar study, identified 27 critical success factors that they classified into four groups, namely “Strategy and Objectives”, “Leadership and Management”, “Human resources” and “External factors”. The commitment of senior management in the lean transformation is underlined in almost all studies. Dombrowski and Mielke [4] highlighted the leadership as a cornerstone for engaging employees in continuous improvement initiatives, something that they consider a critical factor for introducing a lean production system. In the present paper, the focus is on the role of high level management in the successful implementation of lean manufacturing. The work is based on a systematic literature review and a number of interviews conducted in various manufacturing companies in the UK.