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A go-to-market (GTM) strategy is the way in which a company brings a product to market. It generally includes a business plan outlining the target audience, marketing plan, and sales strategy. Each product and market are different, therefore each GTM strategy should be thoroughly thought out, mapping a market problem and solution a product offers. (Source: https://blog.hubspot.com/sales/gtm-strategy)
The go-to-market (GTM) plan is a subset of the marketing plan and addresses how to execute on a specific growth strategy. Every company, regardless of size, should have a marketing plan. A go-to-market plan is only needed if you are looking to expand into new markets, sell new products (services), or do both. (Source: https://www.chiefoutsiders.com/blog/go-to-market-plan-template)
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