The 'problem' of Gibraltar has been a constant source of diplomatic tension between Britain and Spain for over three hundred years. Franco himself described the Rock as 'a dagger in the spine of Spain', and it was during his dictatorship that Spain's diplomatic campaign to recover Gibraltar reached its height with the closing of the frontier in 1969. Given this background, it has long been assumed by historians and commentators that relations between Gibraltar and its Spanish neighbour have also been strained. Gareth Stockey rejects this assumption, and demonstrates that relations across the frontier had in fact been cordial for most of the period of British occupation of the Rock. The focus of this study is the Gibraltar-Spanish frontier. Rather than seeing the frontier as a physical entity -- separating Gibraltar from its Spanish neighbour -- the frontier is viewed as a process, through which the communities on either side of it fostered intimate social, cultural, political and economic links. Instead of creating a distinct and definable Gibraltarian 'identity' in this period -- an identity which has since become a key argument in Gibraltar's calls for self-determination -- the frontier instead served to blur this identity, and infuse the Gibraltarians with an array of Spanish cultural influences. Ironically, given his stated desire to see the Rock returned to Spain, it was Franco's policy of closing the Gibraltar frontier which hardened attitudes on both sides and made a solution to the Gibraltar 'problem' unlikely in the extreme.