Concrete is a substantial substance and it can be used in a variety of ways in interior design. It can be used as a work surface but it is very heavy and not for the faint hearted. I think one would tire of it quickly and it more of a statement of intent than a liveable practical solution. On the other hand, a concrete screed floor is highly desirable and stylish. if poured and treated properly it does not crack. There are no joins gaps or joints and it is easy to keep clean. It has a very stark look and is at odds with the more romantic of settings. However its very simplicity is appealing and when polished and indeed coloured, it can lend a dramatic look to a room. I would say it’s really only for the ground floor of a house and possibly at its best in a kitchen or downstairs bathroom setting. It can be softened by using a lot of natural fibres in the curtains and window dressing and in fact contrasting the uber modern of concrete with a warmer decorative silk or linen in the room will serve to highlight the distinct look of the concrete floor. The use of wood around the area in particular lends a stylish and creative edge to your design. A concrete feature wall can be used in a kitchen that has wooden units for example.
Concrete is very much in line with the trend for an industrial aesthetic. This can be set against using steel and/or glass elements to add more depth and lightness since concrete is a heavy grounded look. I would put a lot of plants in such a scheme to bring some of the outside in. I would also suggest some bright lighting in vibrant colours. The furniture here can veer towards the traditional since a battered leather Chesterfield would work well on a concrete floor. Velvet also would be a good choice to give your space the patina of age in this most urban and modern of settings. A bold print on curtains is a good idea as well as art work and a display of ceramics. This will enhance and counter the grey concrete, especially if you reference the sixties when concrete was the new fashionable thing in architecture.
Use this most functional of materials to give a sharp and sleek feel to your room but don’t forget to flesh out the design with some older pieces and softer elements to make it unique but liveable.