The Lullaby Factory is the transformation of an awkward exterior space at Great Ormond Street Hospital for Children (GOSH), landlocked by buildings, into a secret world that cannot be seen except from inside the hospital and cannot be heard by the naked ear, only by tuning in to its radio frequency or from a few special listening pipes. The multi-phased redevelopment of GOSH, in London's Bloomsbury area, means that the recently completed Morgan Stanley Clinical Building (part of the Mittal Children's Medical Centre) and the 1930s Southwood Building currently sit very close together. The Southwood Building is due to be demolished in 15 years or so, but in the intervening period large windows in the west elevation of the MSCB look directly onto a pipe-ridden brickwork facade, with the gap between the two less than one metre in places. In early 2011 GOSH held a competition for an intervention in the space to improve the existing view or create a new, more positive landscape. Our winning competition entry proposed that the eastern façade of the Southwood Building, with its oodles of mysterious pipes and plant, was actually the Lullaby Factory, where gentle lullabies are manufactured and released to create a calming and uplifting environment for the young patients to recover in. Our proposal was mindful of the fact that the space between the two buildings is very tight and any attempt to cover up the pipework would have resulted in reducing the sense of space and the amount of daylight reaching inside the surrounding buildings. Our approach was therefore to re-imagine the older, rundown façade as the best version of itself. We wanted to accept and celebrate its qualities and oddities; and rather than hiding what is difficult, create something unique and site-specific. The Lullaby Factory is a fantasy landscape reaching ten storeys in height and 43 metres in length. Aesthetically the design was inspired by the mix of a romantic vision of industry and the highly crafted beauty and complexity of musical instruments. The design incorporates gauges and taps reclaimed from a hospital boiler house that was being decommissioned. Completed in October 2012 to coincide with the inhabitation of the MSCB, the project consists of two complimentary elements: the physical factory that appears to carry out the processes of making lullabies, and the soundscape. Composer Jessica Curry recorded a brand new lullaby especially for the project, which children can engage with through listening pipes peering over the café balcony or from their wards by using the bedside radio. The intention is for the project to inspire engagement at GOSH in a variety of ways. The Lullaby Factory was funded by Great Ormond Street Hospital Children’s Charity as part of the investment in the Morgan Stanley Clinical Building. The installation adds to the hospital’s arts programme, Go Create! which makes a vital contribution to the healing environment and the hospital experience GOSH provide for patients, visitors and staff.