diff --git a/src/types.jl b/src/types.jl
index c6f065f9..e54d2c52 100644
--- a/src/types.jl
+++ b/src/types.jl
@@ -20,16 +20,17 @@ const STATE_LOST_PZ    = UInt8(7)
 const STATE_LOST_Z     = UInt8(8)
 
 # Always SOA
-struct Coords{S,V,Q}
+struct Coords{S,V,Q,W}
   state::S # Array of particle states
   v::V     # Matrix of particle coordinates
   q::Q     # Matrix of particle quaternions if spin else nothing 
-  function Coords(state, v, q)
+  weight::W     # Array of particle weights if weighted else nothing
+  function Coords(state, v, q, weight)
     if !isnothing(q) && eltype(v) != eltype(q)
       error("Cannot initialize Coords with orbital coordinates of type $(eltype(v))
              and quaternion coordinates of type $(typeof(q)).")
     end
-    return new{typeof(state),typeof(v),typeof(q)}(state, v, q)
+    return new{typeof(state),typeof(v),typeof(q),typeof(weight)}(state, v, q, weight)
   end
 end
 
@@ -45,42 +46,44 @@ Adapt.@adapt_structure Coords
 
 get_N_particle(bunch::Bunch) = size(bunch.coords.v, 1)
 
-function Bunch(N::Integer; p_over_q_ref=NaN, t_ref=0., species=Species(), spin=false)
+function Bunch(N::Integer; p_over_q_ref=NaN, t_ref=0., species=Species(), spin=false, weight=nothing)
   v = rand(N,6)
   q = spin ? rand(N,4) : nothing
   state = similar(v, UInt8, N)
   state .= STATE_ALIVE
-  return Bunch(species, p_over_q_ref, t_ref, Coords(state, v, q))
+  return Bunch(species, p_over_q_ref, t_ref, Coords(state, v, q, weight))
 end
 
-function Bunch(v::AbstractMatrix, q=nothing; p_over_q_ref=NaN, t_ref=0., species=Species())
+function Bunch(v::AbstractMatrix, q=nothing, weight=nothing; p_over_q_ref=NaN, t_ref=0., species=Species())
   size(v, 2) == 6 || error("The number of columns must be equal to 6")
   N_particle = size(v, 1)
   state = similar(v, UInt8, N_particle)
   state .= STATE_ALIVE
-  return Bunch(species, p_over_q_ref, t_ref, Coords(state, v, q))
+  return Bunch(species, p_over_q_ref, t_ref, Coords(state, v, q, weight))
 end
 
-function Bunch(v::AbstractVector, q=nothing; p_over_q_ref=NaN, t_ref=0., species=Species())
+function Bunch(v::AbstractVector, q=nothing, weight=nothing; p_over_q_ref=NaN, t_ref=0., species=Species())
   length(v) == 6 || error("Bunch accepts a N x 6 matrix of N particle coordinates,
                             or alternatively a single particle as a vector. Received 
                             a vector of length $(length(v))")
-  return Bunch(reshape(v, (1,6)), q; p_over_q_ref=p_over_q_ref, t_ref=t_ref, species=species)
+  return Bunch(reshape(v, (1,6)), q, weight; p_over_q_ref=p_over_q_ref, t_ref=t_ref, species=species)
 end
 
-struct ParticleView{B,T,S,V,Q}
+struct ParticleView{B,T,S,V,Q,W}
   index::Int
   species::Species
   p_over_q_ref::B  
   t_ref::T   
   state::S
   v::V
-  q::Q    
+  q::Q
+  weight::W
   ParticleView(args...) = new{typeof.(args)...}(args...)
 end
 
 function ParticleView(bunch::Bunch, i=1)
   v = bunch.coords.v
   q = bunch.coords.q
-  return ParticleView(i, bunch.species, bunch.p_over_q_ref, bunch.t_ref, bunch.coords.state[i], view(v, :, i), isnothing(q) ? q : view(q, :, i))
+  weight = bunch.coords.weight
+  return ParticleView(i, bunch.species, bunch.p_over_q_ref, bunch.t_ref, bunch.coords.state[i], view(v, :, i), isnothing(q) ? q : view(q, :, i), isnothing(weight) ? weight : weight[i])
 end
\ No newline at end of file
diff --git a/test/runtests.jl b/test/runtests.jl
index 7fefaea6..e245ae87 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -33,7 +33,7 @@ function test_matrix(
   v = transpose(@vars(D1))
   state = similar(v, UInt8, 1)
   state .= STATE_ALIVE
-  coords = Coords(state, v, nothing)
+  coords = Coords(state, v, nothing, nothing)
 
   # Set up kernel chain and launch!
   BeamTracking.launch!(coords, kernel_call)
@@ -60,7 +60,7 @@ function test_matrix(
     q = repeat([1.0 0.0 0.0 0.0], 2)
     state = [STATE_ALIVE STATE_ALIVE]
     @test @ballocated(BeamTracking.launch!(coords, $kernel_call; use_KA=false), 
-    setup=(coords = Coords(copy($state), copy($v), copy($q)))) == 0
+    setup=(coords = Coords(copy($state), copy($v), copy($q), nothing))) == 0
   end
 end
 
@@ -104,7 +104,7 @@ function test_map(
   q = TPS64{D10}[1 0 0 0]
   state = similar(v, UInt8, 1)
   state .= STATE_ALIVE
-  coords = Coords(state, v, q)
+  coords = Coords(state, v, q, nothing)
 
   # Set up kernel chain and launch!
   BeamTracking.launch!(coords, kernel_call)
@@ -121,7 +121,7 @@ function test_map(
     q = repeat([1.0 0.0 0.0 0.0], 2)
     state = [STATE_ALIVE STATE_ALIVE]
     @test @ballocated(BeamTracking.launch!(coords, $kernel_call; use_KA=false), 
-    setup=(coords = Coords(copy($state), copy($v), copy($q)))) == 0
+    setup=(coords = Coords(copy($state), copy($v), copy($q), nothing))) == 0
   end