Interest in clitics originates probably from their special character. As elements which are neither words nor affixes but share some of their properties, they are an especially fruitful ground to test grammatical theories. Such properties include phonological shape, allomorphy, cooccurence restrictions, position in the sentence, and semantic interpretation, thus covering a wide range of phenomena that affect all grammatical components. It is not at all clear whether the notion «clitic» corresponds to some linguistic primitive (or several), although some clitic-related categories, like clitic group as a prosodic category, have been proposed. The general properties of what has been classified as a clitic also varies, depending on the language and the specific clitic analyzed.

The papers collected in this volume are concerned with a wide range of topics which reflect the work that is being conducted at present in this field. They have been written by specialists who devote their current work to describing the intonational systems of Romance languages and to discussing some of the theoretical questions posed in intonational phonology. I trust the volume will contribute to broaden the empirical and theoretical studies of prosody within the Romance area and will spark further interest and inquiry into the area of intonational phonology.

This special volume presents a series of papers which all deal with the semantics of nominal expressions.
It has long been clear that the relatively simple picture of the relationship between syntactic category and semantic type on which all noun phrases denote generalized quantifiers, while perhaps feasible to maintain, is an idealization that does little to advance our understanding of the great richness and variety in the semantics of nominals that is attested in the world’s languages. In the last thirty years, this picture has grown progressively more complex along at least two dimensions that we would like to emphasize here.
It should be evident that the study of the semantics of nominals continues to offer many interesting avenues to explore. There is still much work to be done to clarify what exactly incorporation consists in –to what extent it is syntactically and semantically homogeneous cross-linguistically, and what its status is within a model of grammar which pursues simplicity and economy (Van Valin 1999). Work on incorporation and related phenomena has forced rethinking about how semantic composition is achieved and how broad the semantic typology of nominals might be; it also has consequences for our understanding of argument structure. Another rich area involves the sortal domain of noun semantics –some of the papers in this volume present perhaps unexpected proposals for the sortal category of noun phrases, with interesting extensions in the empirical coverage of semantic theory. Yet a third area pointed to by the contributions to this volume involve the discourse-pragmatic aspects of meaning that are conventionalized in the interpretations of noun phrases –perhaps the area in greatest need of development.

This fourth volume of Catalan Journal of Linguistics  is devoted to a topic discussed at length in the literature but which nevertheless remains a challenge for any view of phonology: the morphology-phonology interaction. The papers collected address two related issues, the role of morphological information in phonology and the role of phonological information in morphology.
The contributions to this volume raise many interesting questions concerning morphophonemics from different points of view. In the articles some answers to these questions are suggested. One is the search for a more restrictive and coherent grammar to account for alternations. Another one is the existence of certain symmetries between the morphological and the prosodic/phonological level. Yet another one is the role of paradigms and subparadigms (patterns and subpatterns) in phonology and morphology. Unavoidably many other questions remain unresolved and have to be left for future research: What are the consequences of Freedom of Analysis and of Richness of the Base in OT? How can we integrate and limit paradigms and subparadigms in a particular linguistic analysis? Hopefully, this volume sets out further paths to explore.

Generative grammar addressed for the first time acquisition as a central issue in the study of grammar. This perspective has given rise over the years to a considerable body of work, mainly on first language acquisition, but also on second language acquistion, bilingual acquisition, and the acquisition by children affected by SLI. If we assume continuity, i.e. that all stages in acquisition reflect possible natural languages, we must posit a mutual dependency between grammatical theory and the facts of acquisition. On the one hand, theories about particular languages should pass the proof against data from acquisition. On the other hand, acquisition data may provide a source of evidence for deciding among alternative theories of language.
Within the past twenty years, Romance languages have been an increasing focus of research for theories of language, and the literature on the acquisition of Romance has grown steadily during this time. The moment thus seemed ripe to unify the efforts of several scholars working on the acquisition of Romance languages and devote a special issue of CatJL to the acquisition of Romance, taking into consideration the double perspective just mentioned. We thank the authors and reviewers for making this project possible. The volume deals with the acquisition of the phonology, morphology and syntax in Catalan, French, Portuguese, Romanian and Spanish. The papers dealing with phonology focus on two main topics: the acquisition of prosodic constituents and the interface between phonology and morphology. The prosodic constituents examined are: the syllable (Demuth & Kehoe on consonant clusters in French; Prieto & Bosch Baliarda on codas in Catalan) and the foot (Goad & Buckley on the relevance of the foot in Québec French). The morpho-phonological interface is treated by Fikkert & Freitas (on the relevance of allophony and allomorphy for the acquisition of the Portuguese vowel system), and Lleó (on the dependence of plural marking on phonological acquisition). The papers dealing with syntax focus on the acquisition of pronominal clitics (Babyonyshev & Marin on clitic production in Romanian and Pirvulescu on clitic omission in French) and verb and wh- movement (Costa & Loureiro on verb raising in Portuguese, Hamann on wh- movement in French).
All the papers in this volume show the relevance of formal linguistics to issues in acquisition, focusing on the relationship between representation and acquisition from different perspectives and in different modules of the grammar.