This chapter establishes the chronology of the street markets’ development, focusing on their growth and spread, and their legal position. The street markets were not entirely outside the law but not nor were they clearly within it, unlike London’s authorised markets (the wholesale markets such as Smithfield and Billingsgate). The chapter covers three phases: the period to 1867, when the markets expanded in the absence of clear legal frameworks; the 1860s when two initiatives (a law that threatened to eliminate street selling, and an attempt to rehouse it off the streets in the monumental Columbia Market) confirmed by their failure the status quo of the street markets’ informality; and the period to 1939 during which informality persisted under the supervision of the Metropolitan Police, and despite the introduction of licensing in 1927.