Yoast SEO automatically generates and injects schema markup into your WordPress site's HTML without requiring manual intervention. When you install Yoast (free or premium), it creates a Schema Graph that includes Organization schema (from your site settings), WebPage schema for all pages, Article schema for posts, and Breadcrumb schema if you enable breadcrumbs in Yoast's settings. For most WordPress sites, the default Yoast schema covers 70-80% of what Google needs. You configure the foundation by going to Yoast SEO → Settings → Site representation, where you define whether your site represents a person or organization, add your logo, and set social profiles. This feeds directly into your Organization schema output. Yoast Premium adds more granular control. You get the Schema tab in the post editor where you can specify Article types (NewsArticle, BlogPosting, etc.), define FAQ blocks, and add HowTo structured data. The Premium version also lets you create custom schema templates for specific post types or page templates, which matters if you run a real estate site, recipe blog, or e-commerce store with product reviews. If Yoast's built-in schemas don't cover your needs—like if you need LocalBusiness schema with specific opening hours, Event schema, or Product schema—you have three options: use Yoast's API filters to programmatically add schema (requires developer knowledge), install a complementary plugin like Schema Pro or WP Schema Pro that extends Yoast's output, or manually add JSON-LD script tags in your theme's header or footer. At Ottawa SEO, we typically use Yoast for baseline schema and layer specialized plugins only when clients need vertical-specific markup like JobPosting or Course schemas. The key mistake we see is people installing multiple schema plugins that conflict with each other, creating duplicate or contradictory markup. Google's Rich Results Test tool will show you exactly what schema Yoast is outputting, so validate your live pages there before assuming you need additional plugins. Most local service businesses in Ottawa do fine with Yoast's default schema plus a LocalBusiness plugin for NAP consistency.