How do you get two business systems to talk to each other?

Three routes, in order of preference: a native integration the vendors already support, a connector platform such as Power Automate, or a custom build. Take the highest one available, because the cost is not in creating the connection but in maintaining it for the next five years.

The problem worth solving is double entry, and it is more expensive than it looks. When the same information is typed into two systems, you pay three times: the minutes spent re-keying, the errors that inevitably creep in, and the arguments that follow when the two systems disagree about what a customer was quoted. That third cost is the largest and is almost never counted, because it shows up as a difficult conversation rather than a line item.

Native integration is always the first thing to check, and it is surprisingly often available and unused. Vendors build connections to the systems their customers commonly run, so an accounting platform will typically connect to the major job-management, point-of-sale and payment products, and a CRM will connect to the common marketing and email tools. This is the cheapest and most durable route because the vendor maintains it: when either product changes, keeping the integration working is their problem rather than yours. Before designing anything, ask both vendors what they already support.

Where nothing native exists, a connector platform is usually the next step, and most Microsoft 365 businesses already have one. Power Automate connects a large catalogue of common business applications without custom code, and comparable services exist independently. The trade is that you now own the connection: when a vendor changes something, your flow breaks and somebody has to fix it. That is manageable and it should be a conscious commitment rather than a surprise.

Custom integration, written against each system's API, is the last resort and occasionally the right one. It suits a genuinely unusual requirement or an unsupported combination, and it delivers exactly what you specify. It also carries the highest ongoing cost, needs someone who can maintain it, and becomes a liability if that person leaves. If you go this way, insist the work is documented and that the documentation lives with the business rather than in a contractor's head.

Two design decisions matter more than the method. First, which system is the source of truth for each piece of information, because two systems that both allow editing will diverge, and reconciling them afterwards is far harder than deciding upfront. Customer contact details are owned by one system and mirrored to the other, not maintained in both. Second, how often the data moves: real time is not automatically better, and a nightly sync is cheaper, simpler and easier to repair, so reserve real-time for cases where staleness genuinely costs something.

Test with the awkward records rather than the tidy ones, because the tidy ones always work. Every business has customers with no email address, jobs with characters that break exports, records created before a field became mandatory, and duplicate entries nobody has merged. Those are the cases that will hit the integration in week one, so they are the ones to run through it before go-live rather than after.

Plan for failure and monitoring at the same time, because a silently broken integration is worse than none. When it works, people stop checking, and when it stops, nobody notices until a customer does. Build an alert on failure, give the integration a named owner, and confirm before you start who fixes it, since a connection sitting between two vendors invites both to point at the other.

Watch the cost model on connector platforms, because it differs from most software and catches people out. Many price on runs or actions rather than users, so an integration firing on every record change can generate far more volume than a person would guess from watching it work. Check how yours is metered before building something that triggers constantly, and prefer a scheduled batch where the timing genuinely does not matter.

The honest caveat is that integration is sometimes the wrong answer to the right question. If two systems do overlapping jobs badly, connecting them preserves both and adds a dependency; consolidating onto one may be cheaper and simpler, even allowing for the migration. Ask whether you need these two systems talking or whether you need one of them, and be honest about the answer before anyone builds anything. If you want the options weighed against what you already run, call 1800 456 567.