This review is an attempt to look at the picture of the foreign participation and local development in Northeast India as revealed by the assessed research and original documentation. It distinguishes a discovery catalogue from a research core of eight research publications that are analysed in substantive full-text sections. Official statistics are accompanied by a documentary enterprise case, a documented supplementary public-web search and a design-specific appraisal and restricted-evidence sensitivity analysis. Recorded equity for seven northeastern states is recorded at US$36.62 million for October 2019 to June 2026, which is around 0.0101% of the matched national total, excluding Sikkim. Complementary needs are identified in regional diagnostics, which include needs related to border processes, logistics, standards and production capacities. While foreign-enterprise impact evaluations answer questions about the actual impact, scenario and macroeconomic studies address questions related to the potential impact. The case of the bamboo-biorefinery in Assam provides some evidence of participation and early implementation, operator-reported production at the trial stage, and financing pressures and lack of local-outcome measurement. It has a corporate history which must be distinguished from transactions with its parent company. The contribution is a regional application of known investment-stage, geographical, measurement and inference FDI quality channels. Some priorities that are proposed are: Linked project records, verified operation, local supplier and worker outcomes, and evaluation of public support. Studies that cannot be accessed don't affect the findings. The absence of full texts, unmeasured outcomes and unestablished attribution are considered to be different limitations, and no region-wide effect size is inferred.