Sustaining crop production and productivity in sub-Saharan Africa requires the availability and use of quality seed of improved varieties by smallholder farmers. The private sector has been considered as the best way to sustain seed supply and crop productivity. Unfortunately, the private sector’s share in the seed production and delivery in sub-Saharan Africa countries has not been very substantial for decades. As a consequence, farmer access to quality seed of recently released varieties remains very low. This manuscript analyzes the experiences of informal seed producers who graduated to formal private seed enterprises to understand the effectiveness of the support they receive to become viable seed ventures. We used comparative research methods to analyze the qualitative and quantitative data collected to understand the underlying mechanisms. The findings showed that the analyzed seed enterprises started with as little as about USD 300 and have already multiplied over tenfold their initial capital. They benefited from a wide variety of supports, e.g., quality seed production, marketing, partnerships, and value chain development trainings and infrastructures, from extension workers, research centers, national and international NGOs, and the other private seed enterprise operators like large public seed enterprises and agro-dealers. The seed enterprises are producing pre-basic, basic, and certified seed of cereals and self-pollinated legume crops delivered directly to farmers, institutional markets, and agro-dealers. The seed production data have been increasing for the past three years with an area expanding from about 30 ha to over 150 ha per year for chickpea. The seed production and delivery practices being employed are smallholder farmer-based practices that are environmentally friendly. For sustainable and reliable seed production and delivery systems in sub-Saharan Africa, a bold step is needed whereby the informal seed production entities are nurtured and upgraded into formal certified seed production ventures that deliver social and economic benefits to the promotors and the communities.