With less than 4,500 of its population of around 600,000 living overseas in 2013, the Solomon Islands ranks 138th in the world for diaspora formation. At these levels the scale of the diaspora as a proportion of population (0.8 percent) remains lower than it was in the early 20th century, when more than 5,000 Solomon islanders were compulsorily repatriated from Queensland under early Australian Commonwealth legislation. This working paper retraces and reframes the history of Solomon Islands labour mobility and diaspora formation since the 1850s, considering it in relation to the wider institutional and macro-regulatory machineries of three phases or regimes of economic, trade and mobility regulation. These regimes are referred to in this paper as: 1.liberal imperial, 2. national territorial and 3. International neoliberal. We argue that Solomon Islanders’ participation in labour mobility has been substantial under all three phases, but that international mobility and diaspora formation only developed significantly under the liberal imperial regime. Even then, however, its development proved precarious. The ways regional actors and governments acting within the different regimes have framed and segmented labour markets continue to powerfully shape mobility and diaspora outcomes. The paper concludes with a discussion of the implications of the situation to date for future economic development and security in Solomon Islands.