diff --git a/applications/test/labelRanges/Test-labelRanges.C b/applications/test/labelRanges/Test-labelRanges.C
index b1bdb47f37..d986523796 100644
--- a/applications/test/labelRanges/Test-labelRanges.C
+++ b/applications/test/labelRanges/Test-labelRanges.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2017 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011 OpenFOAM Foundation
@@ -143,6 +143,39 @@ int main(int argc, char *argv[])
         Info<< nl;
     }
 
+
+    {
+        range.reset(5, 5);
+        Info<< nl << "Tests on " << range << nl;
+
+        Info<< "first   " << range.first() << nl
+            << "last    " << range.last() << nl
+            << "min     " << range.min() << nl
+            << "max     " << range.max() << nl
+            << "after   " << range.after() << nl
+            << "*begin  " << *range.begin() << nl
+            << "*end    " << *range.end() << nl;
+
+        range += 3;
+        Info<< "increase size " << range << nl;
+
+        range -= 3;  // Probably not a great idea
+        Info<< "decrese size " << range << nl;
+
+        auto iter = range.begin();
+
+        Info<< "iter: " << *iter << nl;
+        ++iter;
+
+        Info<< "iter: " << *iter << nl;
+
+        iter += 3;
+        Info<< "iter: " << *iter << nl;
+    }
+
+
+    Info<< "\nEnd\n" << endl;
+
     return 0;
 }
 
diff --git a/src/OpenFOAM/primitives/ranges/labelRange/labelRange.C b/src/OpenFOAM/primitives/ranges/labelRange/labelRange.C
index ff4f9ab652..e625cdcd80 100644
--- a/src/OpenFOAM/primitives/ranges/labelRange/labelRange.C
+++ b/src/OpenFOAM/primitives/ranges/labelRange/labelRange.C
@@ -198,18 +198,20 @@ Foam::labelRange Foam::labelRange::subset0(const label size) const
 }
 
 
-// * * * * * * * * * * * * * * * Friend Operators  * * * * * * * * * * * * * //
+// * * * * * * * * * * * * * * * IOstream Operators  * * * * * * * * * * * * //
 
 Foam::Istream& Foam::operator>>(Istream& is, labelRange& range)
 {
+    label start, size;
+
     is.readBegin("labelRange");
-    is  >> range.start_ >> range.size_;
+    is >> start >> size;
     is.readEnd("labelRange");
 
-    if (range.size_ < 0)
-    {
-        range.size_ = 0;  // No negative sizes
-    }
+    if (size < 0) size = 0;  // No negative sizes
+
+    range.setStart(start);
+    range.setSize(size);
 
     is.check(FUNCTION_NAME);
     return is;
@@ -218,7 +220,6 @@ Foam::Istream& Foam::operator>>(Istream& is, labelRange& range)
 
 Foam::Ostream& Foam::operator<<(Ostream& os, const labelRange& range)
 {
-    // Only write as ASCII for now
     os  << token::BEGIN_LIST
         << range.start() << token::SPACE << range.size()
         << token::END_LIST;
diff --git a/src/OpenFOAM/primitives/ranges/labelRange/labelRange.H b/src/OpenFOAM/primitives/ranges/labelRange/labelRange.H
index 4c65dd4d92..fbb3027e85 100644
--- a/src/OpenFOAM/primitives/ranges/labelRange/labelRange.H
+++ b/src/OpenFOAM/primitives/ranges/labelRange/labelRange.H
@@ -31,6 +31,7 @@ Description
 
 SourceFiles
     labelRange.C
+    labelRangeI.H
 
 \*---------------------------------------------------------------------------*/
 #ifndef labelRange_H
@@ -45,15 +46,11 @@ namespace Foam
 {
 
 // Forward Declarations
-class labelRange;
 class Istream;
 class Ostream;
 template<class T> class List;
 template<class T> class MinMax;
 
-Istream& operator>>(Istream& is, labelRange& range);
-Ostream& operator<<(Ostream& os, const labelRange& range);
-
 /*---------------------------------------------------------------------------*\
                          Class labelRange Declaration
 \*---------------------------------------------------------------------------*/
@@ -122,7 +119,7 @@ public:
 
         //- An identity range corresponding to (map[i] == i), or with
         //- an optional start index, so that (map[i] == i+start)
-        //  The order of parameters is as per the Foam::identity() function.
+        //  The parameter order as per the Foam::identity() function.
         inline static labelRange identity
         (
             const label len,
@@ -135,33 +132,18 @@ public:
         //- Change the start position
         inline void setStart(const label i) noexcept;
 
-        //- Change the size
+        //- Change the size, enforcing non-negative size.
         inline void resize(const label n) noexcept;
 
         //- Change the size - alias for resize()
         inline void setSize(const label n) noexcept;
 
-        //- Decrease the size by 1, but never below 0.
-        inline void decrement() noexcept;
-
-        //- Increase the size by 1.
-        inline void increment() noexcept;
-
         //- Reset to zero start and zero size
         inline void clear() noexcept;
 
         //- Is the range empty?
         inline bool empty() const noexcept;
 
-        //- Return the range as a list of labels
-        List<label> labels() const;
-
-        //- Adjust the start to avoid negative indices.
-        //  The size is decreased accordingly, but will never become negative.
-        //  Eg, adjusting (-10, 15) becomes (0,5).
-        //  adjusting (-20, 15) becomes (0,0)
-        void adjust() noexcept;
-
         //- Is the range non-empty?
         inline bool valid() const noexcept;
 
@@ -171,24 +153,31 @@ public:
         //- The effective size of the range
         inline label size() const noexcept;
 
-        //- The (inclusive) lower value of the range - same as start(), first()
-        inline label min() const noexcept;
-
-        //- The (inclusive) upper value of the range - same as last()
-        inline label max() const noexcept;
+        //- The value before the start of the range
+        inline label before() const noexcept;
 
         //- The (inclusive) lower value of the range - same as start()
         inline label first() const noexcept;
 
+        //- The (inclusive) lower value of the range - same as start(), first()
+        inline label min() const noexcept;
+
         //- The (inclusive) upper value of the range - same as max()
         inline label last() const noexcept;
 
-        //- The value before the start of the range
-        inline label before() const noexcept;
+        //- The (inclusive) upper value of the range - same as last()
+        inline label max() const noexcept;
 
         //- The value after the last element in the range
+        //  This is identical to the value of cend()
         inline label after() const noexcept;
 
+        //- Adjust the start to avoid negative indices.
+        //  The size is decreased accordingly, but will never become negative.
+        //  Eg, adjusting (-10, 15) becomes (0,5).
+        //  adjusting (-20, 15) becomes (0,0)
+        void adjust() noexcept;
+
         //- Reset start and size, enforcing non-negative size.
         //  \return true if the updated range is valid (non-empty).
         inline bool reset(const label start, const label size) noexcept;
@@ -206,6 +195,9 @@ public:
         //- Return true if the (global) value is located within the range
         inline bool found(const label value) const noexcept;
 
+        //- Return the range as a list of labels
+        List<label> labels() const;
+
         //- Return true if the ranges overlap.
         //  Optional test for ranges that also just touch each other
         bool overlaps(const labelRange& range, bool touches=false) const;
@@ -230,19 +222,12 @@ public:
         labelRange subset0(const label size) const;
 
 
-        //- Return const_iterator to element in the range,
-        //- with bounds checking.
-        //  \return iterator at the requested position, or end() if it is
-        //      out of bounds
-        inline const_iterator at(const label localIndex) const;
-
-
     // Member Operators
 
         //- Return element in the range, without bounds checking
-        inline label operator[](const label localIndex) const noexcept;
+        inline label operator[](const label i) const noexcept;
 
-        //- Return true if the (global) value is located within the range.
+        //- Return true if the global value is located within the range.
         //  Behaviour identical to found() - usable as a predicate
         inline bool operator()(const label value) const noexcept;
 
@@ -250,10 +235,16 @@ public:
         inline label operator++() noexcept;
         inline label operator++(int) noexcept;
 
+        //- Increase the size by n.
+        inline label operator+=(const label n) noexcept;
+
         //- Decrease the size by 1, but never below 0.
         inline label operator--() noexcept;
         inline label operator--(int) noexcept;
 
+        //- Decrease the size by n, but never below 0.
+        inline label operator-=(const label n) noexcept;
+
 
     // STL iterator
 
@@ -269,7 +260,7 @@ public:
                 const label&
             >
         {
-            //- The current (global) index value
+            //- The global value
             label value_;
 
         public:
@@ -277,20 +268,31 @@ public:
         // Constructors
 
             //- Construct from range at given local index.
-            //  If the local index is out of range (eg, negative),
-            //  this creates the 'end' iterator
+            //  An out-of-range index (eg, negative) creates an 'end' iterator
             inline const_iterator(const labelRange* range, const label i=0);
 
         // Member Operators
 
-            //- Return the current (global) value
-            inline label operator*() const;
+            //- Return the (global) value
+            inline label operator*() const noexcept;
 
-            inline const_iterator& operator++();
+            //- Prefix increment, no range checking
+            inline const_iterator& operator++() noexcept;
+
+            //- Postfix increment, no range checking
             inline const_iterator operator++(int);
 
-            inline bool operator==(const const_iterator& iter) const;
-            inline bool operator!=(const const_iterator& iter) const;
+            //- Arbitrary increment, no range checking
+            inline const_iterator& operator+=(const label n) noexcept;
+
+            //- Arbitrary decrement, no range checking
+            inline const_iterator& operator-=(const label n) noexcept;
+
+            //- Test for equality of values
+            inline bool operator==(const const_iterator& iter) const noexcept;
+
+            //- Test for inequality of values
+            inline bool operator!=(const const_iterator& iter) const noexcept;
         };
 
 
@@ -302,18 +304,19 @@ public:
         //  The value returned is guaranteed to be the same as start()
         inline const_iterator cbegin() const;
 
-        //- A const_iterator set to beyond the end of the range
+        //- A const_iterator set to 1 beyond the end of the range.
+        //  The value returned is the same as after()
         inline const const_iterator cend() const;
 
-        //- A const_iterator set to beyond the end of the range
+        //- A const_iterator set to 1 beyond the end of the range.
+        //  The value returned is the same as after()
         inline const const_iterator end() const;
 
-
-    // IOstream Operators
-
-        friend Istream& operator>>(Istream& is, labelRange& range);
-        friend Ostream& operator<<(Ostream& os, const labelRange& range);
-
+        //- Return const_iterator to a position within the range,
+        //- with bounds checking.
+        //  \return iterator at the requested position, or end() for
+        //      out of bounds
+        inline const_iterator at(const label i) const;
 };
 
 
@@ -335,6 +338,15 @@ public:
 template<class> struct labelRangeOp;
 
 
+// IOstream Operators
+
+//- Read labelRange from Istream as (start size) pair, enforce no negative size
+Istream& operator>>(Istream& is, labelRange& range);
+
+//- Write labelRange to Ostream as (start size) pair
+Ostream& operator<<(Ostream& os, const labelRange& range);
+
+
 // Global Operators
 
 inline bool operator==(const labelRange& a, const labelRange& b) noexcept
@@ -344,7 +356,7 @@ inline bool operator==(const labelRange& a, const labelRange& b) noexcept
 
 inline bool operator!=(const labelRange& a, const labelRange& b) noexcept
 {
-    return (a.first() != b.first() || a.size() != b.size());
+    return !(a == b);
 }
 
 
diff --git a/src/OpenFOAM/primitives/ranges/labelRange/labelRangeI.H b/src/OpenFOAM/primitives/ranges/labelRange/labelRangeI.H
index d5006d5c80..5258366378 100644
--- a/src/OpenFOAM/primitives/ranges/labelRange/labelRangeI.H
+++ b/src/OpenFOAM/primitives/ranges/labelRange/labelRangeI.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2017-2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -43,12 +43,10 @@ inline Foam::labelRange::labelRange
     start_(start),
     size_(size)
 {
-    if (size_ < 0)
-    {
-        size_ = 0;  // No negative sizes
-    }
+    if (size_ < 0) size_ = 0;  // No negative sizes
 }
 
+
 inline Foam::labelRange::labelRange
 (
     const label start,
@@ -86,14 +84,14 @@ inline Foam::labelRange::const_iterator::const_iterator
 {}
 
 
-inline Foam::label Foam::labelRange::const_iterator::operator*() const
+inline Foam::label Foam::labelRange::const_iterator::operator*() const noexcept
 {
     return value_;
 }
 
 
 inline Foam::labelRange::const_iterator&
-Foam::labelRange::const_iterator::operator++()
+Foam::labelRange::const_iterator::operator++() noexcept
 {
     ++value_;
     return *this;
@@ -109,21 +107,37 @@ Foam::labelRange::const_iterator::operator++(int)
 }
 
 
+inline Foam::labelRange::const_iterator&
+Foam::labelRange::const_iterator::operator+=(const label n) noexcept
+{
+    value_ += n;
+    return *this;
+}
+
+
+inline Foam::labelRange::const_iterator&
+Foam::labelRange::const_iterator::operator-=(const label n) noexcept
+{
+    value_ -= n;
+    return *this;
+}
+
+
 inline bool Foam::labelRange::const_iterator::operator==
 (
     const const_iterator& iter
-) const
+) const noexcept
 {
-    return (this->value_ == iter.value_);
+    return (value_ == iter.value_);
 }
 
 
 inline bool Foam::labelRange::const_iterator::operator!=
 (
     const const_iterator& iter
-) const
+) const noexcept
 {
-    return (this->value_ != iter.value_);
+    return (value_ != iter.value_);
 }
 
 
@@ -139,14 +153,6 @@ inline Foam::labelRange::const_iterator Foam::labelRange::cbegin() const
 }
 
 
-inline Foam::labelRange::const_iterator
-Foam::labelRange::at(const label localIndex) const
-{
-    // The constructor handles out-of-range properly
-    return const_iterator(this, localIndex);
-}
-
-
 inline const Foam::labelRange::const_iterator Foam::labelRange::end() const
 {
     return const_iterator(this, -1);
@@ -159,6 +165,13 @@ inline const Foam::labelRange::const_iterator Foam::labelRange::cend() const
 }
 
 
+inline Foam::labelRange::const_iterator
+Foam::labelRange::at(const label i) const
+{
+    return const_iterator(this, i);
+}
+
+
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 inline Foam::labelRange Foam::labelRange::identity
@@ -191,19 +204,6 @@ inline void Foam::labelRange::setSize(const label n) noexcept
 }
 
 
-inline void Foam::labelRange::decrement() noexcept
-{
-    --size_;
-    if (size_ < 0) size_ = 0;  // No negative sizes
-}
-
-
-inline void Foam::labelRange::increment() noexcept
-{
-    ++size_;
-}
-
-
 inline void Foam::labelRange::clear() noexcept
 {
     start_ = size_ = 0;
@@ -234,19 +234,19 @@ inline Foam::label Foam::labelRange::start() const noexcept
 }
 
 
-inline Foam::label Foam::labelRange::min() const noexcept
+inline Foam::label Foam::labelRange::before() const noexcept
+{
+    return start_ - 1;
+}
+
+
+inline Foam::label Foam::labelRange::first() const noexcept
 {
     return start_;
 }
 
 
-inline Foam::label Foam::labelRange::max() const noexcept
-{
-    return start_ + size_ - 1;
-}
-
-
-inline Foam::label Foam::labelRange::first() const noexcept
+inline Foam::label Foam::labelRange::min() const noexcept
 {
     return start_;
 }
@@ -258,9 +258,9 @@ inline Foam::label Foam::labelRange::last() const noexcept
 }
 
 
-inline Foam::label Foam::labelRange::before() const noexcept
+inline Foam::label Foam::labelRange::max() const noexcept
 {
-    return start_ - 1;
+    return start_ + size_ - 1;
 }
 
 
@@ -279,10 +279,7 @@ inline bool Foam::labelRange::reset
     start_ = start;
     size_  = size;
 
-    if (size_ < 0)
-    {
-        size_ = 0;  // No negative sizes
-    }
+    if (size_ < 0) size_ = 0;  // No negative sizes
 
     return size_;
 }
@@ -313,18 +310,15 @@ inline bool Foam::labelRange::reset
 
 inline bool Foam::labelRange::found(const label value) const noexcept
 {
-    return (value >= this->first() && value <= this->last());
+    return (size_ && start_ <= value && (value - start_) < size_);
 }
 
 
 // * * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * //
 
-inline Foam::label Foam::labelRange::operator[]
-(
-    const label localIndex
-) const noexcept
+inline Foam::label Foam::labelRange::operator[](const label i) const noexcept
 {
-    return start_ + localIndex;
+    return start_ + i;
 }
 
 
@@ -348,7 +342,8 @@ inline Foam::label Foam::labelRange::operator++(int) noexcept
 
 inline Foam::label Foam::labelRange::operator--() noexcept
 {
-    decrement();
+    --size_;
+    if (size_ < 0) size_ = 0;  // No negative sizes
     return size_;
 }
 
@@ -356,9 +351,26 @@ inline Foam::label Foam::labelRange::operator--() noexcept
 inline Foam::label Foam::labelRange::operator--(int) noexcept
 {
     const label old(size_);
-    decrement();
+    --size_;
+    if (size_ < 0) size_ = 0;  // No negative sizes
     return old;
 }
 
 
+inline Foam::label Foam::labelRange::operator+=(const label n) noexcept
+{
+    size_ += n;
+    return size_;
+}
+
+
+inline Foam::label Foam::labelRange::operator-=(const label n) noexcept
+{
+    size_ -= n;
+    if (size_ < 0) size_ = 0;  // No negative sizes
+    return size_;
+}
+
+
+
 // ************************************************************************* //