Technical SEO optimization means making your site fast, crawlable, and structurally sound so search engines can index and rank it properly. Start with Core Web Vitals: aim for Largest Contentful Paint under 2.5 seconds, First Input Delay under 100ms, and Cumulative Layout Shift under 0.1. Use PageSpeed Insights and Chrome's Lighthouse to identify bottlenecks, then compress images, enable browser caching, minify CSS/JavaScript, and consider a CDN. Ensure Google can crawl your site efficiently. Submit an XML sitemap through Google Search Console, use a logical URL structure without parameters when possible, and implement proper internal linking so no page is more than three clicks from your homepage. Check your robots.txt file isn't blocking important pages. Fix any crawl errors, 404s, or redirect chains showing in Search Console. Mobile-friendliness isn't optional. Google indexes mobile-first, so test your site on actual devices and use responsive design. Avoid intrusive interstitials and ensure tap targets are adequately spaced. Implement HTTPS across your entire site. It's a ranking signal and builds trust. Set up proper canonical tags to prevent duplicate content issues, especially if you have URL parameters or multiple versions of pages. Use hreflang tags if you serve different languages or regional content. Structured data markup helps Google understand your content. Add Schema.org markup for your business type, articles, products, FAQs, or reviews. Validate it with Google's Rich Results Test. At Ottawa SEO, we run monthly technical audits across our 500-plus domain portfolio using Screaming Frog and Search Console. The most common issues we fix are orphaned pages with no internal links, slow server response times on shared hosting, and missing alt text on images. Technical SEO isn't one-and-done; you need ongoing monitoring because CMS updates, new plugins, or hosting changes can break things. Prioritize fixes by potential traffic impact, not just error count.