While it was true of the early gentrification literature that it was overly descriptive it is

now possible that the literature has become too theoretical. After the numerous empirical

accounts of gentrification a theoretical framework which made sense of these

developments within a wider arena was necessary for the literature to get any further.

The theoretical nature of much of the gentrification literature (Bridge, 1994, Smith,

1979, 1991, 1996 and Hamnett, 1991) supports the earlier view that gentrification has

become an orthodoxy which some writers like Lees and Bondi (1995) and Clark (1994)

have sought to synthesise, arguably to the benefit of the subject.


In this regard the field of gentrification studies appears to be unable to attain an ordering

or repeatable and coherent set of theories which may be applied to policy guidance and

insights into the process. The value of the knowledge attached to studying gentrification

is related to its ability to say something about the way our various urban environments

are structured. That they are relatively unstructured may be a reasonable conclusion to

draw from the schisms within the debates.


Theory also plays a crucial role in the measurement and perception of social phenomena

through methodological tools (Atkinson, 1994) and the impingement of theory on

method or more particularly extent of measured manifestation has been noted (Bourne,

1993 and Galster and Peacock, 1986). A good example of the relationship between

theory and observation may be given by citing Bourne’s use of the census to measure

the extent of gentrification where he showed that use of income as a measurement




underestimated gentrification while use of educational attainment overestimated its



These points demonstrate the need for the careful working out, in hypothetical terms, of

those factors that one believes to be involved in the gentrification process. If one takes a

constructivist view of the research process it is important to understand that a selection

of priorities and factors in theoretical terms directly affects the operationalisation and

measurement of the phenomenon under consideration. This also demonstrates the need

for a strong definition of gentrification. Atkinson (1995) discussed the need for a strong

definition that could be used to delineate between what is and is not gentrification by

stressing those factors which were contextual and those which appeared universally in

its manifestation.


While it is clear that there is as much divergence within and between cities as countries

the existence of a dramatic difference between the gentrification of Britain and Europe

and that of North America has been debated by Lees (1994) and Smith (1991). The

importance of this debate is in its wider implications for the way in which one

conceptualises cross-cultural differences and the ways in which one can overcome the

complexities of comparison.


Lees has countered a need to remain contextually aware (1994) with an evolutionary

comparative study (Lees and Carpenter, 1995) of the gentrification process in London,

New York and Paris. This approach may be criticised on a number of counts. While

Lees and Bondi agree with Beauregard (1986) that gentrification is often explained in

terms of ‘specific instances’ to ‘broad statements’ Lees and Carpenter adopt such an

approach in their analysis of these three arbitrarily chosen cities. Little is explained that

might reveal the underlying dynamics of a comparative process since the areas chosen,

Park Slope, New York, Barnsbury, London and the Marais in Paris, are remarkably

similar in their route to gentrification. The result is that gentrification is again revealed

as a homogenous process with little cultural differentiation. Lost then is the potential to

reveal a divergent picture that is seen as an important project by some gentrification

commentators (Lees, 1994, Van Weesep and Musterd, 1991) who see the emergence of

a more complex picture of gentrification. This takes us back to Smith and Williams view

that the;

“preoccupation with the description of gentrification means that we have little sense

of the contextual and compositional forces that ‘produce’ this process” (Williams,


These difficulties, expressed in terms of a need to ‘fit’ the gentrification of one country

with another, may yet be synthesised through an examination of the processes contingencies and constant factors. Both relativistic and universalistic accounts of the

process suffer from the criticism that they are either overly restrictive or too general

respectively. A mediation between these two theoretical positions is clearly desirable. In

order to achieve a truly comparative study of the process of gentriflcation it is necessary

for a reconciliation of both contextual and overarching features to be taken into any

account (Atkinson, 1995).


Smith’s rent gap theory of the gentriflcation process was developed in an attempt to

understand the way in which capital restructuring had led to the gentriflcation of certain

areas of the city at a particular point in time. Smith defined the rent gap as;

“the disparity between the potential ground rent level and the actual ground rent

capitalized under the present land use…the rent gap is produced primarily by capital

depreciation (which diminishes the proportion of ground rent able to be capitalized)

and also by continued urban development and expansion.” (Smith, 1979b:545)

Smith’s work has been very influential in the various attempts that have been made to

understand the central dynamics behind gentriflcation. It must be understood that the

rent gap is not restricted to the explanation of gentriflcation, in Smith’s own words it is

‘a general theory of a very specific set of urban processes’ (Smith, 1991:53).


A Value Gap

Hamnett (1984, 1986) developed an explanation of gentriflcation which is very similar

to Smith’s work. It appears at first sight that Hamnett and Williams’ differences are

based upon their location in two different cultural contexts, in which the exact details

and dynamics of the gentriflcation process have diverged in their manifestation. Such

differences, if accepted, give added weight to any claim that gentriflcation diverges

between locations across the Atlantic.


Clark describes the value gap as; “a disparity between the ‘vacant possession value’ of a property and its ‘tenanted

investment value’. The measure of the vacant possession value of a property is its

sale price to an owner occupier. The measure of the tenanted investment value of a

property is a multiple of its annual rental income as rented property, i.e. the present

value of future rental income as reflected in the sale price between two landlords.”

(Clark, 1992:17)

The difference between the two theories lies in the distinction that they make between

land rent and building value, also apparently related to cultural differences from where

the theories originate.


These gaps indicate divergences in the way in which gentrification has occurred over

time and space yet they also point out the way in which gentrification has remained a

recognisable phenomenon for all its differentiation.


It may be considered a measure of some success that an attempt has been made to relate

the value and rent gaps (Clark, 1991, 1994). However, there remains a lack of consensus

within these theoretical areas. Smith is an emissary of the production based school of

explanation and any debate over the complementarity of the two theories has been

submerged by Smith’s own assertion of the primacy of his own work. In his own words;

“the rent-gap theory remains valid, but that for us to understand both its insights as

well as its limitations, the theory cannot remain isolated but must be connected to a

much more complicated discussion of urban change.” (Smith in Van Weesep and

Musterd, 1991:53)


This point is echoed by Van Weesep (1994) when he asks that the study of this

complex urban phenomenon be rooted in context and in a greater understanding of the

complexities of urban life. It is worrying, however, that these repetitive calls for an

understanding of the complex and chaotic appear as rhetoric, when little has been

done within the literature to expand the empirical base while theorising is constantly

undertaken with no seeming input into policy.


Smith (1979) asserts the existence of two pivotal concepts which form the basis of the

theory, these are 1) the systematic disinvestment in the inner city as a corollary to

suburban expansion and 2) a gap between capitalized ground rent and the potential

ground rent that could be extracted under the highest and best use. Smith assumes the

real world to fit around the theory but two things appear wrong, first, suburban

expansion has all but ceased in many cities while the inner city remains under invested

and simultaneously invested in and, second, as Smith’s preconditions have altered,

gentriflcation has continued such that one cannot explain gentriflcation in terms of those

essential conditions.


Cultural differentiation is not the only weak point of the theory; little theory may be

valid at all times in all places yet Smith argues that his theory ‘remains valid’. Rather it

remains valid when x, y, and z apply; surely they do not. Musterd and van Weesep

(1991) argue that “by explaining the essentials (points 1 and 2 above), this theory will

have the widest applicability” (Musterd and van Weesep, 1991:13). Yet nowhere do

Smith or Musterd and van Weesep argue why these ‘essentials’ are indeed universal or,

even, why they are essential. This is as dogmatic a position to adopt as Smith’s claim

that the fundamental weakness of consumption based theory (particularly Ley) was

deterministic because it suggested that to be correct it must assert that “individual

preference change in unison…internationally” (Smith, 1979:540). This debate points out

one of the fundamental dichotomies in the literature about those elements of

gentriflcation which are contextual and those which are found in all examples of its



These debates and attempts at reconciliation demonstrate a dramatic tension around

what is considered to be an adequate explanation of the gentriflcation process. Both

consumption and production side explanations of the phenomenon have failed to

recognise the importance of the operationalisation of their ideas within an empirical

framework. While both Saunders (1981) and Clark appear to agree on the need for

empirical verification or falsification it appears lacking in the literature.

Interestingly Smith invokes Clark’s work as the way forward for gentriflcation theory;


“We should stop asking the one-dimensional question: ‘Which theory of

gentrification is true, the rent-gap theory, the post-industrial restructuring theory, the

consumer demand for amenities theory, or the institutionalist theory?’ and start

asking ‘If it is so that there is empirical support for all these theories, can we arrive

at an understanding of the ways in which they stand in a logical relation of

complementarity.” (Clark in Smith, 1991:60)

In Smith’s latest foray (1996) he persists in stressing the fundamental basis of

gentrification in production within the context of New York and widens his view to

include case studies in Budapest, Amsterdam and Paris. Perhaps the main reservation

one might have with Smith is his self-location as a radical in emphasising his

production-side arguments as both novel and new and then, simultaneously, adopting

those parts of consumption theory which serve his overall argument (Atkinson, 1997).