'All that is solid', wrote Marx in 1848, 'melts into air'. He was reflecting on what happens when the certainties that give our life structure and meaning are inverted.

He was referring to the effects of capitalism, but he might have been talking about any one of the seismic shifts we have experienced in health services in recent years.

Marx's interests are currently exercising the minds of maverick financial commentators. There might be, heaven help us, some resonance for understanding how to manage the revolutionary changes in the NHS, changes that reflect those found elsewhere: the technological revolution; enhanced consumer expectations; and shifting relations between managers, clinicians and patients.

As the market takes shape and takes hold, the health service is composed of competing services of varying sizes. As health is increasingly commodified, the values that motivate the workforce and underpin the NHS as a universal service free at the point of delivery are being contested.

Cultural changes

IT systems promise to revolutionise the speed at which patient histories can be retrieved and services booked. Our understanding of hospitals as centres of local services is being challenged. Primary care is extending its scope; its boundaries with social care are merging and bleeding in the name of promoting health and well-being.

Clinicians are taking on new roles and leaving behind old ones. The line between management and clinical practice is blurring and senior positions - such as consultants in public health - are now open to medics and non-medics alike. In addition, as health services and local authorities collaborate, hybrid professions are growing that bridge nursing and social work, creating challenges for managers across organisations with different cultures.

The changes are not just structural, they are cultural. The reasons why we chose to work in the NHS 20, 10 or even five years ago are unlikely to correspond with the demands of the service today. Mergers and changes in organisations - such as the separation of provider from commissioning functions in PCTs - can be destabilising for managers as well as the workforce for whom they are responsible, and on whom they rely.

Shared values

Bringing about lasting change is challenging. Gaining mastery over a system with so many variables might seem like the way to go, but perhaps the opposite is true. Rather than trying to grasp the wet bar of soap, perhaps the way to approach strategy in the midst of such chaos is to identify shared values and set the direction of travel, recognising that the mode of transport and the route you wish to take might change, even if the destination is well understood.

In City and Hackney, we have the most overweight children in England and we are tasked with engineering a strategy to achieve a healthy weight for all. The temptation to tie ourselves into targets and structures alone is strong, but the complexity of the task demands something much more fluid. We are working hard to establish a set of shared values. Where predictions and trajectories impose linearity on the chaos of people's lives, we are working with the emerging realities of the communities we serve, the organisations within which we work and the imperatives of policy. We are hopeful that this will bring the changes we need.

Oaks fall in the eye of the storm, willows bend and thrive. Remaining flexible and accepting the unknowable might initially make us anxious, but might also keep us upright and effective in times of change. As certainties dissolve, success will not be found in absolutes, but in keeping focused on the means as well as the ends.