In this Graffiti 4D series, passersby are caught in moments in time to layer the forth dimention (time) over the multiple layers of graffiti/art in public places in Barcelona, Spain. Graffiti is a continuous conversation with present and future artists who care to participate. I participated in the conversation by including and capturing people who shared the same moment in time with me. It's amazing how many of the people 'matched' and seemed to fit the graffiti serendipitously.