diff --git a/Project.toml b/Project.toml
index 9cd9b22..55f4c28 100644
--- a/Project.toml
+++ b/Project.toml
@@ -20,7 +20,7 @@ BenchmarkTools = "0.5"
 IntervalSets = "0.5.1"
 InvertedIndices = "1.0"
 LazyStack = "0.0.7, 0.0.8"
-NamedDims = "0.2.21"
+NamedDims = "0.2.27"
 OffsetArrays = "0.10, 0.11, 1.0"
 Tables = "0.2, 1"
 julia = "1"
diff --git a/README.md b/README.md
index 5f8cc7e..481311b 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # AxisKeys.jl
 
-[![Build Status](https://travis-ci.org/mcabbott/AxisKeys.jl.svg?branch=master)](https://travis-ci.org/mcabbott/AxisKeys.jl)
+[![Build Status](https://travis-ci.org/mcabbott/AxisKeys.jl.svg?branch=master)](https://travis-ci.com/mcabbott/AxisKeys.jl)
 
 <!--<img src="docs/readmefigure.png" alt="block picture" width="400" align="right">-->
 
diff --git a/src/functions.jl b/src/functions.jl
index 134f2d2..b7c36e4 100644
--- a/src/functions.jl
+++ b/src/functions.jl
@@ -92,9 +92,10 @@ end
 
 for (T, S) in [(:KeyedVecOrMat, :KeyedVecOrMat), # KeyedArray gives ambiguities
     (:KeyedVecOrMat, :AbstractVecOrMat), (:AbstractVecOrMat, :KeyedVecOrMat),
-    (:NdaKaVoM, :NdaKaVoM), # These are needed because hcat(NamedDimsArray...) relies on similar()
+    (:NdaKaVoM, :NdaKaVoM),
     (:NdaKaVoM, :KeyedVecOrMat), (:KeyedVecOrMat, :NdaKaVoM),
-    (:NdaKaVoM, :AbstractVecOrMat), (:AbstractVecOrMat, :NdaKaVoM) ]
+    (:NdaKaVoM, :AbstractVecOrMat), (:AbstractVecOrMat, :NdaKaVoM),
+    ]
 
     @eval function Base.vcat(A::$T, B::$S, Cs::AbstractVecOrMat...)
         data = vcat(keyless(A), keyless(B), keyless.(Cs)...)
@@ -118,13 +119,23 @@ for (T, S) in [ (:KeyedArray, :KeyedArray),
         (:KeyedArray, :NamedDimsArray), (:NamedDimsArray, :KeyedArray),
         (:NdaKa, :NdaKa),
         (:NdaKa, :KeyedArray), (:KeyedArray, :NdaKa),
-        (:NdaKa, :AbstractArray), (:AbstractArray, :NdaKa) ]
+        (:NdaKa, :AbstractArray), (:AbstractArray, :NdaKa),
+        ]
 
     @eval function Base.cat(A::$T, B::$S, Cs::AbstractArray...; dims)
-        # numerical_dims = hasnames(A) || hasnames(B) ? ... todo!
-        data = cat(keyless(A), keyless(B), keyless.(Cs)...; dims=dims)
+        numerical_dims, data = if any(hasnames.((A, B, Cs...)))
+            old_names = NamedDims.unify_names_longest(dimnames(A), dimnames(B), dimnames.(Cs)...)
+            new_names = NamedDims.expand_dimnames(old_names, dims)
+            α = NamedDims.dim(new_names, dims)
+            β = cat(keyless(A), keyless(B), keyless.(Cs)...; dims=dims)
+            α, β
+        else
+            α = val_strip(dims)
+            β = cat(keyless(A), keyless(B), keyless.(Cs)...; dims=numerical_dims)
+            α, β
+        end
         new_keys = ntuple(ndims(data)) do d
-            if d in dims
+            if d in numerical_dims
                 key_vcat(keys_or_axes(A,d), keys_or_axes(B,d), keys_or_axes.(Cs,d)...)
             else
                 unify_one(keys_or_axes(A,d), keys_or_axes(B,d), keys_or_axes.(Cs,d)...)
@@ -134,6 +145,8 @@ for (T, S) in [ (:KeyedArray, :KeyedArray),
     end
 
 end
+val_strip(dims::Val{d}) where {d} = d
+val_strip(dims) = dims
 key_vcat(a::AbstractVector, b::AbstractVector) = vcat(a,b)
 key_vcat(a::Base.OneTo, b::Base.OneTo) = Base.OneTo(a.stop + b.stop)
 key_vcat(a,b,cs...) = key_vcat(key_vcat(a,b),cs...)
diff --git a/src/names.jl b/src/names.jl
index 2424567..bb20672 100644
--- a/src/names.jl
+++ b/src/names.jl
@@ -4,7 +4,9 @@ using NamedDims
 
 NdaKa{L,T,N} = NamedDimsArray{L,T,N,<:KeyedArray{T,N}}
 KaNda{L,T,N} = KeyedArray{T,N,<:NamedDimsArray{L,T,N}}
-NdaKaVoM{L,T,N} = NamedDimsArray{L,T,N,<:KeyedVecOrMat}
+
+NdaKaVoM{L,T} = Union{NamedDimsArray{L,T,1,<:KeyedArray}, NamedDimsArray{L,T,2,<:KeyedArray}}
+# NdaKaV{L,T} = NamedDimsArray{L,T,1,<:KeyedArray{T,1}}
 
 # NamedDims now uses dimnames, which behaves like size(A,d), axes(A,d) etc.
 
diff --git a/test/_functions.jl b/test/_functions.jl
index 7925ffe..ef6dee1 100644
--- a/test/_functions.jl
+++ b/test/_functions.jl
@@ -4,6 +4,7 @@ M = wrapdims(rand(Int8, 3,4), r='a':'c', c=2:5)
 MN = NamedDimsArray(M.data.data, r='a':'c', c=2:5)
 V = wrapdims(rand(1:99, 10), v=10:10:100)
 VN = NamedDimsArray(V.data.data, v=10:10:100)
+A3 = wrapdims(rand(Int8, 3,4,2), r='a':'c', c=2:5, p=[10.0, 20.0])
 
 @testset "dims" begin
 
@@ -151,7 +152,11 @@ end
     @test axiskeys(cat(MN,MN, dims=3)) == ('a':1:'c', 2:5, Base.OneTo(2))
     @test axiskeys(cat(M,MN, dims=3)) == ('a':1:'c', 2:5, Base.OneTo(2))
 
-    @test_broken axiskeys(cat(M,M, dims=:r)) # doesn't work in NamedDims either
+    @test axiskeys(cat(M,M, dims=:z)) == ('a':1:'c', 2:5, Base.OneTo(2))
+    @test dimnames(cat(M,M, dims=:z)) == (:r, :c, :z)
+
+    @test axiskeys(cat(A3, A3, dims=:p)) == ('a':1:'c', 2:5, [10.0, 20.0, 10.0, 20.0])
+    @test axiskeys(hcat(A3, A3)) == ('a':1:'c', vcat(2:5,2:5), [10.0, 20.0])
 
 end
 @testset "matmul" begin