Understand what the Chihuahua's noise really means
A Chihuahua barking and lunging at a new dog is usually frightened, not dominant, and an introduction that treats the display as naughtiness will fail him. From his height, every approaching dog is a looming giant, and making noise early is how a very small dog buys himself space. Start far enough away that your Chihuahua can see the new dog and still walk normally, eat treats, and look back at you — that distance is his classroom. Shrink it gradually over several walks, and let his relaxation, not the calendar, decide when the dogs actually meet.
Keep all four feet on the ground
The single most useful rule for Chihuahua introductions is that greetings happen on the ground, with an escape route, never from a pair of arms. A Chihuahua held aloft often feels trapped and may snap at a face that comes close, while the other dog, frustrated by the unreachable target, jumps and scrambles in ways that can genuinely injure a tiny dog. Walk the parallel route with your Chihuahua on a light harness, and when the dogs meet, let him approach and retreat in his own loops. If he chooses to step behind you, that is information to respect by adding distance, not a problem to fix by pushing him forward.
Choose the partner dog with a Chihuahua's safety in mind
Partner selection carries physical stakes for a Chihuahua that it does not for bigger breeds. A calm, dog-savvy adult who greets briefly and disengages is ideal; a boisterous adolescent of any large breed is a poor choice, because one playful paw or body check can fracture small bones even with the friendliest intent. First meetings with much larger dogs deserve extra space and a barrier option, such as walking on opposite sides of a quiet fence line, so your Chihuahua can learn the dog's smell and movement without any chance of contact. Never use a dog park's small-dog chaos as a Chihuahua's introduction to a specific new dog.
Run the close greeting in tiny, controlled steps
When parallel walks are calm, let the Chihuahua make a brief curved approach, sniff for two or three seconds, and be called away for a treat before either dog's excitement builds. Repeat the loop a few times rather than letting one greeting stretch, and watch his body: a loose, wiggly Chihuahua who keeps choosing to go back is enjoying himself, while one who goes still, tucks his tail, or escalates his barking as the other dog nears is done. Handlers of the bigger dog should keep their dog settled and side-on during these exchanges, since a polite partner who simply stands calmly teaches a Chihuahua more than any amount of forced sniffing.
Build a pattern of safe meetings over time
Chihuahuas generalise from experience, so a run of short, safe meetings teaches this breed that new dogs predict good outcomes, while one frightening ambush can set introductions back for months. Keep early friendships one dog at a time, repeat the same calm walk with the same partner, and add indoor time only once the outdoor version is boring, feeding the dogs separately and giving your Chihuahua a high retreat spot the other dog cannot reach. Persistent trembling, snapping on approach, or panic at distances that never shrink is worth a certified trainer's assessment rather than more practice. Everyone who walks your Chihuahua can follow the same plan through KinsLe, where Care Teams records his working distance, his safe partners, and the feet-down rule for every greeting.