I vote for function but I do take style in to consideration. I choose them according to the colour of my dog so they compliment them.

Both dogs have them from red dingo, Ozzy's say's Posh because he is and Ludi's has a swirly pattern on it that suits his colouring.

I had to tick more than one box as the training leads and haltis I used with Zane and Yiannis are black. Zane still has his red lead that I'd used with him since a puppy. Tashi has her red harness and tan leather hound collar. All of them have red Ancol buckle collars for ID with black collars and ID tags for outings.

When I had Ellie I bought her s red diamante collar which suited her perfectly even though she was black/brindle.

I have thought of getting blue for the boys and pink for the girls but as others have said, mostly their covered in mud at least (and God knows what else) so I tend not to be too bothered about colour most of the time.

Having said that I've never had anyone confuse their genders. Nobody has assumed either of the boys are girls and both my girls are too pretty to be boys.

i have to have the collar and lead matching haha! I just bought a halti double ended lead and as it was in black, i had to buy a black collar to go with it although i wanted red...isnt that absolutely ridiculous? now im saying it, i cant believe that i did it hahah!
i need to get out more...
Having said that, i have gone for practicality after choosing purely for style. the sylish collars and leads were useless and in the end was just "paraphanalia" so now its down to basics and functionality

Sadie has to have a pink one 'cos everyone thinks she's male.

Benjie and Louie have leather collars - for the same reason as Labradork - mud. Sadie has a fabric collar but I can't find her a pink leather collar that has no rhinestones or decoration on - I just want a plain pink leather collar that doesn't cost the earth! Lol

But they also have to be strong - 3 strong dogs need strong collars.

Ted has a lupine martingale collar which i chose because he can slip out of others really easily, its also easy to clean. But i did choose the collar and pattern to suit him (black with silver skull and cross bones ) He has now got a matching lead as i needed to replace his rogz one so thought i might as well get the matching set. I did go with what i think are boy colours for his dog games harness which he has one is black and blue and one is black and green So i voted functional but also colour

Have gone for function + colour.

I use the Lupine Combi (and clip) collars, I love the way they are made and their lifetime replacement policy, they go through the wash great and are really tough, and I love the patterns as well!

I have gone down the traditional hound route with mine , they have house collars , which are soft fabric martingales and have their ID tags on , I can grab them in the house if I need to although I havent had to yet !

For walking mine have fishtail leather hound collars, Toms is handmade leather with a sheepskin lining and its the only collar that hasnt rubbed the fur off his neck so it was chosen for function although the colour was chosen to compliment his tiger stripes.
Bella has a red leather collar with flowers on cos she is a girly !

I also have harnesses for when they are long lines as they get less tangled !

I too use Lupine leads , chosen because they are replaced for free for life if they get damaged and wash well.

I make my own dogs collars out of beta, which is strong, hardwearing and very easy to clean, so very practical. It doesn't matter if it gets wet as its dry in seconds and and dirt just wipes off it. I do like to go for colours though.

Cooper had a purple collar when he was a pup but people kept calling him a girl. I then changed to a glow in the dark one, but I overestimated his adult size and it was always huge on him
I then made him a hi viz yellow with black overlay one. It was American hunting style but then I got his flat name tag and it didn't work well so now it's 'normal' style with name tag at the back of the neck. I really like his current collar as it matches with his Julius K9 harness and he is all hi vized up so easily seen.

I made Harry's collar to my mums specs, she wanted brown and black, so I made a a brown and black overlay collar and added a rivet design on it, in American hunting style. I then bought her a brown and lack Doxlock harness for xmas so she would match.

Have voted function and colour, both of our have leather collars and leads, they're practical and hard wearing but comfortable and the leads are comfy for me to use which with two big, strong dogs is important. Chester's is the softest leather I could find anywhere but ended up being quite cheap and though Griffin's was expensive I'm not really expecting to have to replace it. The former is a lemony colour whilst the latter is black, the two compliment their coats though as has been said once they're got wet and muddy the thought I've put into that all seems a bit pointless !

I voted for function and colour.
Flint has a black half check collar and black 6ft lead and a black halti.
Simba has a blue half check, blue 6ft lead and blue halti.
Gemma has a red collar [not half check just normal, but have got her a red half check for when shes a bit older] and a red 6ft lead.

All the leads and collars match, i got them from crufts lol. They are really quite srong and very comfy to hold, the leads can also be halfed in length by using the O ring on the handle