Yemen has diverse ecosystems constituting agroecosystems, deserts, marine, coastal, forests, and wetland ecosystems. These ecosystems have high biological diversity (biodiversity), ranging from avian, fish, and mammals to anthropoids. The country's high species diversity is due to its geographical strategic location at a juncture of three major biogeographic regions: the Pale-arctic, Afro-tropical, and oriental regions. It is the greenest country in the Arabian Peninsula, with the green cover constituting approximately 4.6% of the country's land mass. 

Yemen's ecosystems’ contribution to the national economy and community livelihoods is highly significant. The ecosystems’ contribution is through provision, regulation, support, and cultural functions. In 2012, the economic value of the key ecosystems was estimated at USD 287,829 million. In 2015, it was estimated that over 15 million Yemenis were directly dependent on ecosystems for sustenance. 

An assessment of the status of the key ecosystems in the country reveals that there is widespread degradation for almost all the ecosystems. The ecosystem degradation is evident from deforestation (mangroves and forest), coastal, wadis, and terrace erosion, pollution of the wetland ecosystems, and destruction of the coral reefs. Similarly, species such as large mammals, avians, and fish are being illegally hunted, traded, and harvested at an unprecedented rate. Various factors contribute to widespread ecosystem degradation and species loss, such as: armed conflicts, unsustainable production processes, land use changes, climate change, invasive species, widespread pollution, and illegal trade. These factors are fuelled by underlying aspects, mainly poverty, weak institutional capacity to enforce existing policies and Acts, market distortions due to externalities, and perverse economic incentives amongst others. 

Whilst there is widespread ecosystem degradation and species in the country, from time immemorial, the Yemenis have traditionally sustainably managed their ecosystems to ensure optimal and non-declining flow of ecosystems functions and services. Some of the traditional ecosystem’s management included the Mahjeer rangeland management systems. 

Furthermore, the government of Yemen has taken initiatives to protect, conserve, and sustainably utilise its vital ecosystems. This includes the development of a robust and comprehensive legal framework. The country has various Decrees and Laws. At the center of the Decrees and the Law is the Environment Protection Law No 26 of 1996, which established EIA. 

Another critical step taken by the country to strengthen its national efforts of conserving and protecting its natural assets was the ratification of the United Nations Convention on Biological Diversity (UNCBD) in 1996. Consequently, over the years, Yemen has devotedly developed, submitted, and made operational its NBSAP. The country developed its NBSAP I in 2007-2017 and the NBSAP II in 2011-2020 with robust and high-level national strategic activities. In December 2022, CBD party members endorsed the K-M GBF and collectively agreed to update their existing NBSAPs by aligning their national targets and goals with the GBF targets. This undertaking is thus aimed at fulfilling the party members' decision to update the NBSAP II into NBSAP III. 

Consequently, the country’s NBSAP is a living document that is updated quinquennially following the CBD amendments and based on intensive stakeholders’ consultation processes and lessons learned from the previous NBSAP.